Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2015	Feb. 10, 2016	Jun. 30, 2015
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Entity Registrant Name	Employers Holdings, Inc.
Entity Central Index Key	0001379041
Current Fiscal Year End Date	--12-31
Entity Well Know Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock Shares Outstanding		32,216,480
Entity Public Float			$ 729,797,712
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Available for sale:
Fixed maturity securities at fair value (amortized cost $2,221,100 at December 31, 2015 and $2,186,100 at December 31, 2014)	$ 2,288,500	$ 2,275,700
Equity securities at fair value (cost $137,500 at December 31, 2015 and $97,800 at December 31, 2014)	198,700	172,700
Total investments	2,487,200	2,448,400
Cash and cash equivalents	56,600	103,600
Restricted cash and cash equivalents	2,500	10,800
Accrued investment income	20,600	20,500
Premiums receivable, less bad debt allowance of $12,200 at December 31, 2015 and $7,900 at December 31, 2014	301,100	295,800
Reinsurance recoverable for:
Paid losses	7,700	10,700
Unpaid losses, including bad debt allowance	628,200	669,500
Deferred policy acquisition costs	44,300	44,600
Deferred income taxes, net	67,900	49,700
Property and equipment, net	24,900	21,000
Intangible assets, net	8,500	9,000
Goodwill	36,200	36,200
Contingent commission receivable–LPT Agreement	29,200	26,400
Other assets	40,900	23,500
Total assets	3,755,800	3,769,700
Claims and policy liabilities:
Unpaid losses and loss adjustment expenses	2,347,500	2,369,700
Unearned premiums	308,900	310,800
Total claims and policy liabilities	2,656,400	2,680,500
Commissions and premium taxes payable	52,500	46,300
Accounts payable and accrued expenses	24,100	20,400
Deferred reinsurance gain—LPT Agreement	189,500	207,000
Notes payable	32,000	92,000
Other liabilities	40,500	36,700
Total liabilities	$ 2,995,000	$ 3,082,900
Commitments and contingencies (Note 12)
Stockholders’ equity:
Common stock, $0.01 par value; 150,000,000 shares authorized; 55,589,454 and 54,866,802 shares issued and 32,216,480 and 31,493,828 shares outstanding at December 31, 2015 and 2014, respectively	$ 600	$ 600
Preferred stock, $0.01 par value; 25,000,000 shares authorized; none issued	0	0
Additional paid-in capital	357,200	346,600
Retained earnings	682,000	595,300
Accumulated other comprehensive income, net	83,600	106,900
Treasury stock, at cost (23,372,974 shares at December 31, 2015 and 2014)	(362,600)	(362,600)
Total stockholders’ equity	760,800	686,800
Total liabilities and stockholders’ equity	$ 3,755,800	$ 3,769,700

Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Available for sale:
Fixed maturity securities, amortized cost	$ 2,358,600	$ 2,283,900
Premiums receivable, bad debt allowance	12,200	7,900
Reinsurance recoverables, allowance for unpaid losses	$ 0	$ 0
Stockholders' equity
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	55,589,454	54,866,802
Common stock, shares outstanding (in shares)	32,216,480	31,493,828
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000
Preferred stock, shares issued (in shares)	0	0
Treasury stock, at cost (in shares)	23,372,974	23,372,974
Debt Securities [Member]
Available for sale:
Fixed maturity securities, amortized cost	$ 2,221,100	$ 2,186,100
Equity Securities [Member]
Available for sale:
Fixed maturity securities, amortized cost	$ 137,500	$ 97,800

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues
Net premiums earned	$ 690,400	$ 684,500	$ 642,300
Net investment income	72,200	72,400	70,800
Net realized (losses) gains on investments	(10,700)	16,300	9,500
Other income	200	300	900
Total revenues	752,100	773,500	723,500
Expenses
Losses and loss adjustment expenses	429,400	453,400	463,600
Commission expense	85,400	81,400	78,300
Underwriting and other operating expenses	135,200	129,100	125,300
Interest expense	2,700	3,000	3,200
Total expenses	652,700	666,900	670,400
Net income before income taxes	99,400	106,600	53,100
Income tax expense (benefit)	5,000	5,900	(10,700)
Net income	94,400	100,700	63,800
Comprehensive income
Unrealized (losses) gains during the period (net of tax (benefit) expense of $(16,300), $14,600, and $(17,700) for the years ended December 31, 2015, 2014, and 2013, respectively)	(30,300)	27,100	(32,900)
Reclassification adjustment for realized gains in net income (net of taxes of $(3,700), $5,700, and $3,300 for the years ended December 31, 2015, 2014, and 2013, respectively)	7,000	(10,600)	(6,200)
Other comprehensive (loss) income, net of tax	(23,300)	16,500	(39,100)
Total comprehensive income	$ 71,100	$ 117,200	$ 24,700
Earnings per common share (Note 18):
Basic	$ 2.94	$ 3.19	$ 2.05
Diluted	2.90	3.14	2.00
Cash dividends declared per common share	$ 0.24	$ 0.24	$ 0.24
Net realized (losses) gains on investments
Net realized gains on investments before impairments on fixed maturity and equity securities	$ 6,500	$ 16,800	$ 9,600
Other than temporary impairment recognized in earnings	(17,200)	(500)	(100)
Net realized (losses) gains on investments	$ (10,700)	$ 16,300	$ 9,500

Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Comprehensive Income Parenthetical [Abstract]
Other comprehensive income (loss), unrealized holding gain (loss) on securities arising during period, tax	$ (16,300)	$ 14,600	$ (17,700)
Other comprehensive income (loss), reclassification adjustment for sale of securities included in net income, tax	$ (3,700)	$ 5,700	$ 3,300

Consolidated Statements of Stockholders Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income, Net	Treasury Stock at Cost
Stockholders' equity, shares at Dec. 31, 2012		54,144,453
Stockholders' equity, value at Dec. 31, 2012	$ 539,400	$ 600	$ 326,000	$ 445,900	$ 129,500	$ (362,600)
Stock-based compensation (Note 14), shares		0
Stock-based compensation (Note 14), value	5,600	$ 0	5,600	0	0	0
Stock-options exercised, shares		411,295
Stock options exercised, value	7,400	$ 0	7,400	0	0	0
Vesting of restricted stock units, net of shares withheld to satisfy minimum tax withholding (Note 15), shares		117,156
Vesting of restricted stock units, net of shares withheld to satisfy minimum tax withholding (Note 15), value	(900)	$ 0	(900)	0	0	0
Dividend to common stockholders, shares		0
Dividend to common stockholders, value	7,500	$ 0	0	7,500	0	0
Stockholders' equity, shares at Dec. 31, 2013		54,672,904
Net income for the period	63,800	$ 0	0	63,800	0	0
Change in net unrealized gains on investments, net of taxes	(39,100)	0	0	0	(39,100)	0
Stockholders' equity, value at Dec. 31, 2013	568,700	$ 600	338,100	502,200	90,400	(362,600)
Stock-based compensation (Note 14), shares		0
Stock-based compensation (Note 14), value	6,000	$ 0	6,000	0	0	0
Stock-options exercised, shares		120,494
Stock options exercised, value	2,200	$ 0	2,200	0	0	0
Vesting of restricted stock units, net of shares withheld to satisfy minimum tax withholding (Note 15), shares		73,404
Vesting of restricted stock units, net of shares withheld to satisfy minimum tax withholding (Note 15), value	(600)	$ 0	(600)	0	0	0
Dividend to common stockholders, shares		0
Dividend to common stockholders, value	$ 7,600	$ 0	0	7,600	0	0
Stockholders' equity, shares at Dec. 31, 2014	54,866,802	54,866,802
Net income for the period	$ 100,700	$ 0	0	100,700	0	0
Change in net unrealized gains on investments, net of taxes	16,500	0	0	0	16,500	0
Stockholders' equity, value at Dec. 31, 2014	686,800	$ 600	346,600	595,300	106,900	(362,600)
Stock-based compensation (Note 14), shares		0
Stock-based compensation (Note 14), value	4,600	$ 0	4,600	0	0	0
Stock-options exercised, shares		463,466
Stock options exercised, value	7,600	$ 0	7,600	0	0	0
Vesting of restricted stock units, net of shares withheld to satisfy minimum tax withholding (Note 15), shares		259,186
Vesting of restricted stock units, net of shares withheld to satisfy minimum tax withholding (Note 15), value	(2,700)	$ 0	(2,700)	0	0	0
Dividend to common stockholders, shares		0
Dividend to common stockholders, value	$ 7,700	$ 0	0	7,700	0	0
Stockholders' equity, shares at Dec. 31, 2015	55,589,454	55,589,454
Excess tax benefit from stock-based compensation	$ 1,100	$ 0	1,100	0	0	0
Net income for the period	94,400	0	0	94,400	0	0
Change in net unrealized gains on investments, net of taxes	(23,300)	0	0	0	(23,300)	0
Stockholders' equity, value at Dec. 31, 2015	$ 760,800	$ 600	$ 357,200	$ 682,000	$ 83,600	$ (362,600)

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating activities
Net income	$ 94,400	$ 100,700	$ 63,800
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	8,300	7,000	6,100
Stock-based compensation	4,600	6,000	5,600
Amortization of premium on investments, net	12,800	10,600	9,000
Allowance for doubtful accounts	4,300	800	1,100
Deferred income tax benefit	(5,600)	(500)	(10,800)
Net realized gains (losses) on investments	10,700	(16,300)	(9,500)
Excess tax benefits from stock-based compensation	(1,200)	(1,200)	0
Other operating activities, adjustments to reconcile net income to net cash	100	(300)	(900)
Change in operating assets and liabilities:
Premiums receivable	(9,600)	(17,600)	(57,200)
Reinsurance recoverable on paid and unpaid losses	44,300	71,300	63,800
Federal income taxes recoverable	(3,900)	6,500	(3,700)
Unpaid losses and loss adjustment expenses	(22,200)	39,200	99,000
Unearned premiums	(1,900)	6,800	38,800
Accounts payable, accrued expenses and other liabilities	8,600	12,800	1,800
Deferred reinsurance gain–LPT Agreement	(17,500)	(42,100)	(32,000)
Contingent commission receivable–LPT Agreement	(2,800)	(1,300)	(6,000)
Other	(7,000)	(10,500)	(2,400)
Net cash provided by operating activities	116,400	171,900	166,500
Investing activities
Purchase of fixed maturity securities	(476,900)	(378,000)	(514,200)
Purchase of equity securities	(85,100)	(29,500)	(30,500)
Proceeds from sale of fixed maturity securities	105,400	47,900	52,500
Proceeds from sale of equity securities	34,700	36,500	30,700
Proceeds from maturities and redemptions of investments	323,900	251,100	206,800
Proceeds from sale of fixed assets	0	0	800
Capital expenditures and other	(11,500)	(10,500)	(5,000)
Change in restricted cash and cash equivalents	8,300	(4,200)	(1,200)
Net cash used in investing activities	(101,200)	(86,700)	(260,100)
Financing activities
Cash transactions related to stock-based compensation	4,800	1,600	6,500
Dividends paid to stockholders	(7,700)	(7,600)	(7,500)
Payments on notes payable and capital leases	(60,500)	(11,300)	(11,600)
Excess tax benefits from stock-based compensation	1,200	1,200	0
Net cash used in financing activities	(62,200)	(16,100)	(12,600)
Net (decrease) increase in cash and cash equivalents	(47,000)	69,100	(106,200)
Cash and cash equivalents at the beginning of the period	103,600	34,500	140,700
Cash and cash equivalents at the end of the period	56,600	103,600	34,500
Cash (received) paid for income taxes	12,700	(1,100)	3,900
Cash paid for interest	2,800	3,000	3,300
Schedule of non-cash transactions
Financed property and equipment purchases	$ 300	$ 700	$ 2,300

Basis of Presentation	12 Months Ended
Basis of Presentation	Dec. 31, 2015
Basis of Presentation [Abstract]
Basis of Presentation	Basis of Presentation and Summary of Operations Nature of Operations and Organization Employers Holdings, Inc. (EHI) is a Nevada holding company. Through its wholly owned insurance subsidiaries, Employers Insurance Company of Nevada (EICN), Employers Compensation Insurance Company (ECIC), Employers Preferred Insurance Company (EPIC), and Employers Assurance Company (EAC), EHI is engaged in the commercial property and casualty insurance industry, specializing in workers' compensation products and services. Unless otherwise indicated, all references to the “Company” refer to EHI, together with its subsidiaries. Basis of Presentation The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP). All intercompany transactions and balances have been eliminated in consolidation. The Company considers an operating segment to be any component of its business whose operating results are regularly reviewed by the Company's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance based on discrete financial information. Currently, the Company has one operating segment, workers' compensation insurance and related services. Use of Estimates The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. As a result, actual results could differ from these estimates. The most significant areas that require management judgment are the estimate of unpaid losses and loss adjustment expenses (LAE), evaluation of reinsurance recoverables, recognition of premium revenue, deferred income taxes, and investments. Reclassifications Certain prior period information has been reclassified to conform to the current period presentation.

Changes in Estimates Level 1 (Notes)

12 Months Ended

Dec. 31, 2015

Changes in Estimates [Abstract]

Accounting Changes and Error Corrections

Changes in Estimates

The Company reduced its estimated reserves ceded under the Loss Portfolio Transfer Agreement (LPT Reserve Adjustments) in each of the years 2015, 2014, and 2013 as a result of the determination that adjustments were necessary to reflect observed favorable paid loss trends in each of these years. The following table shows the financial statement impact related to the reduction in estimated reserves ceded under the Loss Portfolio Transfer Agreement (LPT Agreement).



	2015			2014			2013
	(in millions, except per share data)
Change in estimated reserves ceded under the LPT Agreement	$	(10.0	)	$	(46.8	)	$	(27.5	)
Cumulative adjustment to the Deferred Gain⁽¹⁾	(6.4		)	(31.1		)	(19.0		)
Net income impact of change in estimate	6.4			31.1			19.0
EPS impact of change in estimate
Basic	0.20			0.99			0.61
Diluted	0.20			0.97			0.59


(1)	The cumulative adjustments to the Deferred Gain were also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, so that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.

The Company increased its estimate of Contingent commission receivable – LPT Agreement (LPT Contingent Commission Adjustments) in each of 2015, 2014, and 2013 as a result of the determination that adjustments were necessary to reflect observed favorable paid loss trends in each of those years. The following table shows the impact to the Consolidated Statements of Comprehensive Income related to these changes in estimates.



	2015			2014			2013
	(in millions, except per share data)
Cumulative adjustment to the deferred reinsurance gain - LPT Agreement (Deferred Gain)⁽¹⁾	$	(2.6	)	$	(10.8	)	$	(4.3	)
Net income impact of change in estimate	2.6			10.8			4.3
EPS impact of change in estimate
Basic	0.08			0.34			0.14
Diluted	0.08			0.34			0.13


(1)	The cumulative adjustments to the Deferred Gain were also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, so that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.

The Company reallocated reserves from non-taxable periods prior to January 1, 2000 to taxable years, which reduced its effective tax rates, in each of 2015, 2014, and 2013. These changes in estimates were the result of the determination that a reallocation of reserves among accident years was appropriate to address a continuation of observed loss trends in each of those years. The following table shows the financial statement impact of these changes in estimates.



	2015			2014			2013
	(in millions, except per share data)
Reserves reallocated to taxable years	$	56.3		$	13.1		$	27.2
Impact to effective tax rate	(15.4		)%	(3.4		)%	(13.9		)%
Net income impact of change in estimate	$	15.3		$	3.6		$	7.4
EPS impact of change in estimate
Basic	0.48			0.11			0.24
Diluted	0.47			0.11			0.23

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2015

Summary of Significant Accounting Policies [Abstract]

Significant Accounting Policies

Summary of Significant Accounting Policies

Cash and Cash Equivalents

The Company considers all highly liquid investments with an initial maturity of three months or less at the date of purchase to be cash equivalents.

Restricted Cash and Cash Equivalents

Restricted cash and cash equivalents is primarily related to funds held in trust to secure the Company's line of credit and for reinsurance. The Company held $32.7 million and $33.3 million in trust for reinsurance, of which $2.5 million and $6.1 million were classified as restricted cash and cash equivalents at December 31, 2015 and 2014, respectively.

Investments

The Company's investments in fixed maturity securities and equity securities are classified as available-for-sale and are reported at fair value with unrealized gains and losses excluded from earnings and reported as a separate component of equity, net of deferred taxes, in accumulated other comprehensive income.

Investment income consists primarily of interest and dividends. Interest is recognized on an accrual basis, and dividends are recorded as earned at the ex-dividend date. Interest income on mortgage-backed and asset-backed securities is determined using the effective-yield method based on estimated principal repayments. Mortgage-backed securities are adjusted for the effects of changes in prepayment assumptions on the related accretion of discount or amortization of premium of such securities using the retrospective method.

Realized capital gains and losses on investments are determined on a specific-identification basis.

When, in the opinion of management, a decline in the fair value of an equity security below its cost is considered to be “other-than-temporary,” the equity security's cost is written down to its fair value at the time the other-than-temporary decline is identified. The determination of an other-than-temporary decline for debt securities includes, in addition to other relevant factors, a presumption that if the market value is below cost by a significant amount for a period of time, a bifurcation of the write-down may be necessary. If management has the intent to sell the debt security or more likely than not will be required to sell the debt security before its anticipated recovery, the investment is written down to its fair value and the entire impairment is recorded as a realized loss due to credit in the accompanying consolidated statements of comprehensive income. If management does not have the intent to sell or will not be required to sell the debt security but does not expect to recover the amortized cost basis of the debt security, the amount of the other-than-temporary impairment is bifurcated between credit loss and other loss and recorded as a component of realized gains and losses and to other comprehensive income, respectively, in the consolidated statements of comprehensive income. The amount of any write-down is determined by the difference between the cost or amortized cost of the debt security and its fair value at the time the other-than-temporary decline is identified (see Note 6).

Recognition of Revenue and Expense

Revenue Recognition

Premium revenue is recognized over the period of the contract in proportion to the amount of time insurance protection is provided. At the end of the policy term, payroll-based premium audits are performed on substantially all policyholder accounts to determine net premiums earned for the policy year. Earned but unbilled premiums include estimated future audit premiums based on the Company's historical experience. These estimates are subject to changes in policyholders' payrolls, economic conditions, and seasonality, and are continually reviewed and adjusted as experience develops or new information becomes known. Any such adjustments are included in current operations; however, they are partially offset by the resulting changes in losses and LAE, commission expenses, and premium taxes. The Company's premiums receivable on the consolidated balance sheet included $53.5 million and $49.1 million of additional premiums expected to be received from policyholders for final audits at December 31, 2015 and 2014, respectively.

The Company establishes a bad debt allowance on its premiums receivable through a charge included in underwriting and other operating expenses in the accompanying consolidated statements of comprehensive income. This bad debt allowance is determined based on estimates and assumptions to project future experience. After all collection efforts have been exhausted, the Company reduces the bad debt allowance for write-offs of premiums receivable that have been deemed uncollectible. The Company's bad debt allowance was $12.2 million and $7.9 million at December 31, 2015 and 2014, respectively. The Company had write-offs, net of recoveries of amounts previously written off, of $2.4 million, $3.4 million, and $2.5 million for the years ended December 31, 2015, 2014, and 2013, respectively.

Deferred Policy Acquisition Costs

Policy acquisition costs that relate directly to the successful acquisition of new or renewal insurance contracts, including underwriting, policy issuance and processing, medical and inspection, and sales force contract selling are deferred and amortized as the related premiums are earned. Amortization of deferred policy acquisition costs for the years ended December 31, 2015, 2014, and 2013, was $103.9 million, $102.7 million, and $96.9 million, respectively.

A premium deficiency would exist if expected future losses and LAE, expected policyholder dividends, deferred policy acquisition costs, and expected policy maintenance costs, offset by anticipated investment income, exceed the related unearned premiums. A premium deficiency would reduce the value of deferred policy acquisition costs. If the deficiency exceeded the deferred policy acquisition costs, a separate liability would be accrued for the excess deficiency. There was no premium deficiency at December 31, 2015 or 2014.

Unpaid Loss and LAE Reserves

Loss and LAE reserves represent management's best estimate of the ultimate net cost of all reported and unreported losses incurred for the applicable periods, less payments made. The estimated reserves for losses and LAE include the accumulation of estimates for all claims reported prior to the balance sheet date, estimates of claims incurred but not reported, and estimates of expenses for investigating and adjusting all incurred and unadjusted claims (based on projections of relevant historical data). Amounts reported are necessarily subject to the impact of future changes in economic, regulatory and social conditions. Management believes that, subject to the inherent variability in any such estimate, the reserves are within a reasonable and acceptable range of adequacy. Estimates for claims prior to the balance sheet date are continually monitored and reviewed, and as settlements are made or reserves adjusted, the differences are reported in current operations. Salvage and subrogation recoveries are estimated based on a review of the level of historical salvage and subrogation recoveries.

Reinsurance

In the ordinary course of business and consistent with general insurance industry practices, the Company purchases excess of loss reinsurance to protect the Company against the impact of large and/or catastrophic losses in its workers' compensation business. Additionally, the Company is a party to a 100% quota share retroactive reinsurance agreement (see Note 10). This reinsurance reduces the financial impact of such losses on current operations and the equity of the Company. Reinsurance makes the assuming reinsurer liable to the ceding company to the extent of the reinsurance coverage provided. It does not, however, discharge the Company from its liability to its policyholders in the event the reinsurer is unable or unwilling to meet its obligations under its reinsurance agreement with the Company.

Net premiums earned and losses and LAE incurred are stated in the accompanying consolidated statements of comprehensive income after deduction of amounts ceded to reinsurers. Balances due from reinsurers on unpaid losses, including an estimate of such recoverables related to reserves for incurred but not reported losses, are reported as assets and are included in reinsurance recoverables even though amounts due on unpaid losses and LAE are not recoverable from the reinsurer until such losses are paid. Recoverables from reinsurers on unpaid losses and LAE amounted to $628.2 million and $669.5 million at December 31, 2015 and 2014, respectively.

Ceded losses and LAE are accounted for on a basis consistent with those used in accounting for the original policies issued and the terms of the relevant reinsurance agreement.

The 100% quota share retroactive reinsurance agreement was entered into in 1999 by the Nevada State Industrial Insurance System (the Fund) and assumed by EICN, which the Company refers to as the LPT Agreement (see Note 10). Loss expenses are deemed to be 7% of total losses paid and are paid to the Company as compensation for management of the claims under the LPT Agreement. The Company accounts for this transaction as retroactive reinsurance, whereby the initial deferred gain was recorded as a liability in the accompanying consolidated balance sheets as Deferred reinsurance gain–LPT Agreement. This gain is amortized using the recovery method, whereby the amortization is determined by the proportion of actual reinsurance recoveries to total estimated recoveries through the life of the LPT Agreement, and is recorded in losses and LAE incurred in the accompanying consolidated statements of comprehensive income. Any adjustment to the estimated reserves ceded under the LPT Agreement results in a cumulative adjustment to the Deferred Gain, which is also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, such that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.

Additionally, the Company is entitled to receive a contingent profit commission under the LPT Agreement. The contingent profit is equal to 30% of the favorable difference between actual paid losses and LAE and expected paid losses and LAE as established in the LPT Agreement based on losses paid through June 30, 2024. The contingent profit commission is paid every five years beginning June 30, 2004 for the first twenty-five years of the agreement. The Company is paid 30% of the favorable difference between the actual and expected losses and LAE paid at each calculation point. The Company could be required to return any previously received contingent profit commission, plus interest, in the event of unfavorable differences through June 30, 2024. The Company records its estimate of contingent profit commission in the accompanying consolidated balance sheets as Contingent commission receivable–LPT Agreement and a corresponding liability is recorded on the accompanying consolidated balance sheets in Deferred reinsurance gain–LPT Agreement. The Contingent commission receivable–LPT Agreement is reduced as amounts are received from participating reinsurers. In 2014, the Company received $11.7 million in cash related to the contingent profit commission. The related Deferred reinsurance gain–LPT Agreement is amortized using the recovery method. The amortization of the contingent profit commission is determined by the proportion of actual reinsurance recoveries to total estimated recoveries over the life of the contingent profit commission (through June 30, 2024), and is recorded in losses and LAE incurred in the accompanying consolidated statements of comprehensive income. Any adjustment to the contingent profit commission under the LPT Agreement results in a cumulative adjustment to the Deferred Gain, which is also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, such that the Deferred Gain reflects the balance that would have existed had the revised contingent profit commission been recognized at the inception of the LPT Agreement.

Property and Equipment

Property and equipment are stated at cost less accumulated depreciation (see Note 7). Expenditures for maintenance and repairs are charged against operations as incurred.

Electronic data processing equipment, software, furniture and equipment, and automobiles are depreciated using the straight-line method over three to seven years. Leasehold improvements are carried at cost less accumulated amortization. The Company amortizes leasehold improvements using the straight-line method over the lesser of the useful life of the asset or the remaining original lease term, excluding options or renewal periods. Leasehold improvements are generally amortized over three to five years.

Obligations Held Under Capital Leases

Leased property and equipment meeting capital lease criteria are capitalized at the lower of the present value of the related lease payments or the fair value of the leased asset at the inception of the lease. Amortization is calculated using the straight-line method based on the term of the lease and is included in the depreciation expense of property and equipment. See Note 12 for additional disclosures related to capital leases.

Income Taxes

The Company's accounting for income taxes considers the current and deferred tax consequences of all transactions that have been recognized in its consolidated financial statements using the provisions of enacted tax laws. Deferred tax assets and liabilities are determined based on differences between the financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The effect on deferred tax assets and liabilities resulting from a tax rate change affects net income or loss in the period that includes the enactment date of the tax rate change. The Company's income tax returns are subject to audit by the Internal Revenue Service and various state tax authorities. Significant disputes may arise with these tax authorities involving issues of the timing and amount of deductions and allocations of income among various tax jurisdictions because of differing interpretations of tax laws and regulations. The Company periodically evaluates exposures associated with tax filing positions. Although we believe our positions comply with applicable laws, liabilities are recorded based upon estimates of the ultimate outcomes of these matters.

In assessing whether deferred tax assets will be realized, the Company considers whether it is more likely than not that it will generate future taxable income during the periods in which those temporary differences become deductible. The Company considers the scheduled reversal of deferred tax liabilities, tax planning strategies, and projected future taxable income in making this assessment. If necessary, a valuation allowance is established to reduce the deferred tax assets to the amounts that are more likely than not to be realized.

Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk are primarily cash and cash equivalents, investments, premiums receivable, and reinsurance recoverable balances.

Cash equivalents include investments in money market securities and securities backed by the U.S. government. Investments are diversified throughout many industries and geographic regions. The Company limits the amount of credit exposure with any one financial institution and believes that no significant concentration of credit risk exists with respect to cash and cash equivalents and investments.

At December 31, 2015 and 2014, the outstanding premiums receivable balance was generally diversified due to the large number of entities composing the Company's policyholder base and their dispersion across many different industries. The Company also has recoverables from its reinsurers. Reinsurance contracts do not relieve the Company of its obligations to claimants or policyholders. Failure of reinsurers to honor their obligations could result in losses to the Company. The Company evaluates the financial condition of its reinsurers to minimize its exposure to significant losses from reinsurer insolvencies. The Company obtains collateral to mitigate the risks related to reinsurance insolvencies. At December 31, 2015, $3.7 million was collateralized by cash or letters of credit and an additional $1.4 billion was in trust accounts for reinsurance related to the LPT Agreement.

Fair Value of Financial Instruments

Estimated fair value amounts have been determined using available market information and other appropriate valuation methodologies. Judgment is required in developing the estimates of fair value where quoted market prices are not available. Accordingly, these estimates are not necessarily indicative of the amounts that could be realized in a current market exchange. The use of different market assumptions or estimating methodologies may have an effect on the estimated fair value amounts.

The following methods and assumptions were used by the Company in estimating the fair value for financial instruments in the accompanying consolidated financial statements and in these notes for the years ended 2015 and 2014:

Cash and cash equivalents, premiums receivable, accounts payable, and accrued expenses and other liabilities. The carrying amounts for these financial instruments as reported in the accompanying consolidated balance sheets approximate their fair values.

Investments. The estimated fair values for available-for-sale securities generally represent quoted market prices for securities traded in the public marketplace or estimated values for securities not traded in the public marketplace. Additional data with respect to fair values of the Company's investment securities is disclosed in Note 5.

Goodwill and Other Intangible Assets

The Company tests for impairment of goodwill and non-amortizable intangible assets in the fourth quarter of each year. At the end of each quarter, management considers the results of the previous analysis as well as any recent developments that may constitute triggering events requiring the impairment analysis of goodwill and other intangible assets to be updated. The Company has assessed the effects of current economic conditions on the Company's financial condition and results of operations and changes in the Company's stock price and determined that there were no impairments as of December 31, 2015 and 2014.

Intangible assets related to state licenses are not subject to amortization. Intangibles related to insurance relationships will be amortized in proportion to the expected period of benefit over the next three years.

The gross carrying value, accumulated amortization, and net carrying value for the Company's intangible assets, by major class, as of December 31, were as follows:



	2015							2014
	Gross Carrying Value		Accumulated Amortization			Net Carrying Value		Gross Carrying Value		Accumulated Amortization			Net Carrying Value
	(in millions)
State licenses	$	7.7	$	—		$	7.7	$	7.7	$	—		$	7.7
Insurance relationships	9.4		$	(8.6	)	0.8		9.4		$	(8.1	)	1.3
Total	$	17.1	$	(8.6	)	$	8.5	$	17.1	$	(8.1	)	$	9.0

During the years ended December 31, 2015, 2014, and 2013, the Company recognized $0.5 million, $0.7 million, and $0.9 million in amortization expenses, respectively. These amortization expenses are included in the accompanying consolidated statements of comprehensive income in underwriting and other operating expenses. Amortization expense is expected to be as follows:



Year	Amount
	(in millions)
2016	0.4
2017	0.3
2018	0.1
Total	$	0.8

Stock-Based Compensation

The Company issues stock-based payments, which are recognized in the consolidated statements of comprehensive income based on their estimated fair values over the employees' service period (see Note 14).

New Accounting Standards	12 Months Ended
New Accounting Standards	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Standards	New Accounting Standards In April 2015, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) Number 2015-05, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40). The update provides guidance to purchasers to assist in determining whether a cloud computing arrangement includes a software license and how to account for such an arrangement. This update becomes effective for annual reporting periods, including interim periods within those annual periods, beginning after December 15, 2015 and early adoption is permitted. The Company does not expect the adoption to have a material impact on its consolidated financial condition and results of operations. In May 2015, the FASB issued ASU Number 2015-07, Fair Value Measurement (Topic 820). This update removes the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using the net asset value (NAV) per share. Additionally, this update removes the requirement to make certain disclosures for all investments that are eligible to be measured as a practical expedient at fair value using the NAV per share. This update becomes effective for annual reporting periods, including interim periods within those annual periods, beginning after December 15, 2015 and early adoption is permitted. As this update focuses only on disclosures, it will not impact the Company's consolidated financial condition and results of operations. In May 2015, the FASB issued ASU Number 2015-09, Financial Services - Insurance (Topic 944). This update expands the breadth of disclosures that an insurance entity must provide about its short-duration insurance contracts. This expanded disclosure includes the presentation of incurred and paid claims development tables by accident year for a period of up to 10 years. This update becomes effective for annual reporting periods beginning after December 15, 2015 and interim periods beginning after December 15, 2016 and early adoption is permitted. As this update focuses only on disclosures, it will not impact the Company's consolidated financial condition and results of operations. In January 2016, the FASB issued ASU Number 2016-01, Financial Instruments - Overall (Subtopic 825-10). This update replaces the guidance to classify equity transactions with readily determinable fair values into different categories (trading or available-for-sale) and requires equity securities to be measured at fair value with changes in fair value recognized through net income. Additionally, this update eliminates the method and significant assumptions used to estimate the fair value of financial instruments measured at amortized cost. It requires financial instruments to be measured at fair value using the exit notion price. Furthermore, this update clarifies that an evaluation of deferred tax assets related to available-for-sale securities is needed, in combination with and evaluation of other deferred tax assets, to determine if a valuation allowance is required. This update becomes effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company has not yet estimated the full effect that adoption will have on its consolidated financial condition and results of operations.

- Definition

The entire disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6507316

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Direct Effects of a Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6510796

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=56949863&loc=d3e22583-107794

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Indirect Effects of a Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6515603

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=56949863&loc=d3e22580-107794

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.10-01.(b)(6))
-URI http://asc.fasb.org/extlink&oid=27015980&loc=d3e46468-122699

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accounting Change
-URI http://asc.fasb.org/extlink&oid=6503790

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=56949863&loc=d3e22499-107794

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Retrospective Application
-URI http://asc.fasb.org/extlink&oid=6523989

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=51655806&loc=d3e765-108305

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=51655806&loc=d3e725-108305

+ Details

Fair Value of Financial Instruments

12 Months Ended

Dec. 31, 2015

Fair Value of Financial Instruments [Abstract]

Fair Value of Financial Instruments

The carrying value and the estimated fair value of the Company's financial instruments as of December 31, were as follows:



	2015				2014
	Carrying Value		Estimated Fair Value		Carrying Value		Estimated Fair Value
Financial assets	(in millions)
Investments (Note 6)	$	2,487.2	$	2,487.2	$	2,448.4	$	2,448.4
Cash and cash equivalents	56.6		56.6		103.6		103.6
Restricted cash and cash equivalents	2.5		2.5		10.8		10.8
Financial liabilities
Notes payable (Note 11)	$	32.0	$	36.6	$	92.0	$	97.8

Assets and liabilities recorded at fair value on the consolidated balance sheets are categorized based upon the levels of judgment associated with the inputs used to measure their fair value. Level inputs are defined as follows:


•	Level 1 - Inputs are unadjusted quoted market prices for identical assets or liabilities in active markets at the measurement date.


•	Level 2 - Inputs other than Level 1 prices that are observable for similar assets or liabilities through corroboration with market data at the measurement date.


•	Level 3 - Inputs that are unobservable that reflect management's best estimate of what willing market participants would use in pricing the assets or liabilities at the measurement date.

Fair values of available-for-sale fixed maturity and equity securities are based on quoted market prices, where available. These fair values are obtained primarily from third party pricing services, which generally use Level 1 or Level 2 inputs. The Company obtains a quoted price for each security from third party pricing services, which are derived through recently reported trades for identical or similar securities. For securities not actively traded, the third party pricing services may use quoted market prices of similar instruments or discounted cash flow analyses, incorporating inputs that are currently observable in the markets for similar securities. Inputs that are often used in the valuation methodologies include, but are not limited to, broker quotes, benchmark yields, credit spreads, default rates, and prepayment speeds. The Company also performs a quarterly analysis on the prices received from third parties to determine whether the prices are reasonable estimates of fair value, including confirming the fair values of these securities through observable market prices using an alternative pricing source. If differences are noted in this review, the Company may obtain additional information from other pricing services to validate the quoted price. There were no adjustments to prices obtained from third party pricing services as of December 31, 2015 and 2014 that were material to the consolidated financial statements.

If quoted market prices and an estimate determined by using objectively verifiable information are unavailable, the Company produces an estimate of fair value based on internally developed valuation techniques, which, depending on the level of observable market inputs, will render the fair value estimate as Level 2 or Level 3. The Company bases all of its estimates of fair value for assets on the bid price, as it represents what a third-party market participant would be willing to pay in an arm's length transaction.

These methods of valuation will only produce an estimate of fair value if there is objectively verifiable information to produce a valuation. If objectively verifiable information is not available, the Company would be required to produce an estimate of fair value using some of the same methodologies, making assumptions for market-based inputs that are unavailable.

The Company's estimates of fair value for financial liabilities are based on a combination of the variable interest rates for the Company's existing line of credit and other notes with similar durations to discount the projection of future payments on notes payable. The fair value measurements for notes payable have been determined to be Level 2.

The following table presents the items in the accompanying consolidated balance sheets that are stated at fair value and the corresponding fair value measurements.



	December 31, 2015						December 31, 2014
	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
	(in millions)
Fixed maturity securities
U.S. Treasuries	$	—	$	120.2	$	—	$	—	$	166.7	$	—
U.S. Agencies	—		24.4		—		—		39.6		—
States and municipalities	—		854.5		—		—		745.8		—
Corporate securities	—		925.3		—		—		908.3		—
Residential mortgage-backed securities	—		237.9		—		—		288.4		—
Commercial mortgage-backed securities	—		80.3		—		—		65.4		—
Asset-backed securities	—		45.9		—		—		61.5		—
Total fixed maturity securities	$	—	$	2,288.5	$	—	$	—	$	2,275.7	$	—
Equity securities	$	198.7	$	—	$	—	$	172.7	$	—	$	—

The Company had no Level 3 investments during the years ended December 31, 2015 and 2014.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Investments

12 Months Ended

Dec. 31, 2015

Investments [Abstract]

Investments

The cost or amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the Company’s investments were as follows:



	Cost or Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
At December 31, 2015	(in millions)
Fixed maturity securities
U.S. Treasuries	$	116.4	$	3.9	$	(0.1	)	$	120.2
U.S. Agencies	23.0		1.4		—			24.4
States and municipalities	809.4		45.1		—			854.5
Corporate securities	913.4		19.9		(8.0		)	925.3
Residential mortgage-backed securities	231.8		7.1		(1.0		)	237.9
Commercial mortgage-backed securities	81.1		0.2		(1.0		)	80.3
Asset-backed securities	46.0		—		(0.1		)	45.9
Total fixed maturity securities	2,221.1		77.6		(10.2		)	2,288.5
Equity securities	137.5		65.8		(4.6		)	198.7
Total investments	$	2,358.6	$	143.4	$	(14.8	)	$	2,487.2

At December 31, 2014
Fixed maturity securities
U.S. Treasuries	$	160.9	$	5.8	$	—		$	166.7
U.S. Agencies	37.2		2.4		—			39.6
States and municipalities	701.6		44.4		(0.2		)	745.8
Corporate securities	880.7		30.8		(3.2		)	908.3
Residential mortgage-backed securities	278.6		10.6		(0.8		)	288.4
Commercial mortgage-backed securities	65.5		0.5		(0.6		)	65.4
Asset-backed securities	61.6		—		(0.1		)	61.5
Total fixed maturity securities	2,186.1		94.5		(4.9		)	2,275.7
Equity securities	97.8		75.5		(0.6		)	172.7
Total investments	$	2,283.9	$	170.0	$	(5.5	)	$	2,448.4

The amortized cost and estimated fair value of fixed maturity securities at December 31, 2015, by contractual maturity, are shown below. Expected maturities differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties.



	Amortized Cost		Estimated Fair Value
	(in millions)
Due in one year or less	$	113.6	$	115.1
Due after one year through five years	859.3		884.5
Due after five years through ten years	636.9		657.1
Due after ten years	252.4		267.7
Mortgage and asset-backed securities	358.9		364.1
Total	$	2,221.1	$	2,288.5

The following is a summary of investments that have been in a continuous unrealized loss position for less than 12 months and those that have been in a continuous unrealized loss position for 12 months or greater as of December 31, 2015 and 2014.



	December 31, 2015						December 31, 2014
	Estimated Fair Value		Gross Unrealized Losses			Number of Issues	Estimated Fair Value		Gross Unrealized Losses			Number of Issues
Less than 12 months:	(dollars in millions)
Fixed maturity securities
U.S. Treasuries	$	27.4	$	(0.1	)	20	$	—	$	—		—
States and municipalities	—		—			—	20.6		(0.2		)	5
Corporate securities	328.4		(4.7		)	122	109.9		(0.8		)	42
Residential mortgage-backed securities	50.5		(0.8		)	24	—		—			—
Commercial mortgage-backed securities	51.5		(1.0		)	22	—		—			—
Asset-backed securities	34.1		—			27	—		—			—
Total fixed maturity securities	491.9		(6.6		)	215	130.5		(1.0		)	47
Equity securities	35.8		(4.6		)	45	10.1		(0.6		)	15
Total less than 12 months	$	527.7	$	(11.2	)	260	$	140.6	$	(1.6	)	62

Greater than 12 months:
Fixed maturity securities
Corporate securities	$	34.6	$	(3.3	)	15	$	129.4	$	(2.4	)	39
Residential mortgage-backed securities	7.1		(0.2		)	25	44.1		(0.8		)	36
Commercial mortgage-backed securities	—		—			—	31.3		(0.6		)	8
Asset-backed securities	11.1		(0.1		)	4	18.3		(0.1		)	6
Total fixed maturity securities	52.8		(3.6		)	44	223.1		(3.9		)	89
Total greater than 12 months	$	52.8	$	(3.6	)	44	$	223.1	$	(3.9	)	89

Total available-for-sale:
Fixed maturity securities
U.S. Treasuries	$	27.4	$	(0.1	)	20	$	—	$	—		—
States and municipalities	—		—			—	20.6		(0.2		)	5
Corporate securities	363.0		(8.0		)	137	239.3		(3.2		)	81
Residential mortgage-backed securities	57.6		(1.0		)	49	44.1		(0.8		)	36
Commercial mortgage-backed securities	51.5		(1.0		)	22	31.3		(0.6		)	8
Asset-backed securities	45.2		(0.1		)	31	18.3		(0.1		)	6
Total fixed maturity securities	544.7		(10.2		)	259	353.6		(4.9		)	136
Equity securities	35.8		(4.6		)	45	10.1		(0.6		)	15
Total available-for-sale	$	580.5	$	(14.8	)	304	$	363.7	$	(5.5	)	151

Based on reviews of the fixed maturity securities, the Company determined that unrealized losses for the years ended December 31, 2015, 2014, and 2013 were primarily the result of changes in prevailing interest rates and not the credit quality of the issuers. The fixed maturity securities whose fair value was less than amortized cost were not determined to be other-than-temporarily impaired given the severity and duration of the impairment, the credit quality of the issuers, the Company’s intent on not selling the securities, and a determination that it is not more likely than not that the Company will be required to sell the securities until fair value recovers to above amortized cost, or to maturity.

Based on reviews of the equity securities, the Company recognized total impairments of $17.2 million, $0.5 million and $0.1 million in the fair values of 27, seven, and one equity securities primarily as a result of the severity and duration of the change in fair values of those securities as of December 31, 2015, 2014, and 2013, respectively. The remaining unrealized losses on equity securities were not considered to be other than temporary due to the financial condition and near-term prospects of the issuers. The other-than-temporary impairments of equity securities in 2015 were primarily due to the continued downturn in the energy sector during the fourth quarter.

Net realized gains on investments and the change in unrealized gains (losses) on fixed maturity and equity securities are determined on a specific-identification basis and were as follows:



	Years Ended December 31,
	2015			2014			2013
	(in millions)
Net realized gains on investments
Fixed maturity securities
Gross gains	$	0.5		$	1.1		$	0.7
Gross losses	(0.4		)	—			—
Net realized gains on fixed maturity securities	$	0.1		$	1.1		$	0.7
Equity securities
Gross gains	$	8.1		$	15.7		$	9.1
Gross losses	(18.9		)	(0.5		)	(0.3		)
Net realized gains on equity securities	$	(10.8	)	$	15.2		$	8.8
Total	$	(10.7	)	$	16.3		$	9.5

Change in unrealized gain (losses)
Fixed maturity securities	$	(22.2	)	$	23.1		$	(88.8	)
Equity securities	(13.7		)	2.2			28.6
Total	$	(35.9	)	$	25.3		$	(60.2	)

Net investment income was as follows:



	Years Ended December 31,
	2015			2014			2013
	(in millions)
Fixed maturity securities	$	68.8		$	70.7		$	69.5
Equity securities	5.9			4.2			3.8
Cash equivalents and restricted cash	0.1			0.1			0.1
Gross investment income	74.8			75.0			73.4
Investment expenses	(2.6		)	(2.6		)	(2.6		)
Net investment income	$	72.2		$	72.4		$	70.8

The Company is required by various state laws and regulations to keep securities or letters of credit in depository accounts with certain states in which it does business. As of December 31, 2015 and 2014, securities having a fair value of $881.2 million and $783.9 million, respectively, were on deposit. These laws and regulations govern not only the amount but also the type of securities that are eligible for deposit.

Certain reinsurance contracts require Company funds to be held in trust for the benefit of the ceding reinsurer to secure the outstanding liabilities assumed by the Company. The fair value of fixed maturity securities and restricted cash and cash equivalents held in trust for the benefit of the ceding reinsurers at December 31, 2015 and 2014 was $32.7 million and $33.3 million, respectively.

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References + Details

Property and Equipment

12 Months Ended

Dec. 31, 2015

Property and Equipment [Abstract]

Property, Plant and Equipment Disclosure

Property and Equipment

Property and equipment consists of the following:



	As of December 31,
	2015			2014
	(in millions)
Furniture and equipment	$	2.3		$	2.3
Leasehold improvements	4.3			4.4
Computers and software	56.7			46.0
Automobiles	1.2			1.2
	64.5			53.9
Accumulated amortization and depreciation	(39.6		)	(32.9		)
Property and equipment, net	$	24.9		$	21.0

Depreciation and amortization expenses related to property and equipment for the years ended December 31, 2015, 2014, and 2013 were $7.8 million, $6.3 million, and $5.2 million, respectively. Internally developed software costs of $1.2 million and $0.8 million were capitalized during each of the years ended December 31, 2015 and 2014.

Income Taxes

12 Months Ended

Dec. 31, 2015

Income Taxes [Abstract]

Income Taxes

The Company files a consolidated federal income tax return. The insurance subsidiaries pay premium taxes on gross premiums written in lieu of some states' income or franchise taxes.

The provision for income taxes consisted of the following:



	Years Ended December 31,
	2015			2014			2013
Current tax expense:	(in millions)
Federal	$	9.5		$	6.3		$	0.1
State	1.1			0.1			—
Total current tax expense	10.6			6.4			0.1
Deferred federal tax benefit	(5.6		)	(0.5		)	(10.8		)
Income tax expense (benefit)	$	5.0		$	5.9		$	(10.7	)

The difference between the statutory federal tax rate of 35% and the Company's effective tax rate on net income before income taxes as reflected in the consolidated statements of comprehensive income was as follows:



	Years Ended December 31,
	2015			2014			2013
	(in millions)
Expense computed at statutory rate	$	34.8		$	37.3		$	18.6
Dividends received deduction and tax-exempt interest	(8.6		)	(8.8		)	(9.1		)
Pre-Privatization reserve adjustments, excluding LPT	(15.3		)	(3.6		)	(7.4		)
LPT deferred gain amortization	(4.9		)	(8.4		)	(6.6		)
LPT Reserve Adjustment	(2.2		)	(10.9		)	(6.7		)
Other	1.2			0.3			0.5
Income tax expense (benefit)	$	5.0		$	5.9		$	(10.7	)

On January 1, 2000, EICN assumed the assets, liabilities, and operations of the Fund pursuant to legislation passed in the 1999 Nevada Legislature (the Privatization). Prior to the Privatization, the Fund was a part of the State of Nevada and therefore was not subject to federal income tax; accordingly, it did not take an income tax deduction with respect to the establishment of its unpaid loss and LAE reserves. Due to favorable loss experience after the Privatization, it was determined that certain of the pre-Privatization unpaid loss and LAE reserves assumed by EICN as part of the Privatization were no longer necessary and the unpaid loss and LAE reserves were reduced accordingly. Such downward adjustments of pre-Privatization unpaid loss reserves increased GAAP net income by $15.3 million, $3.6 million, and $7.4 million for the years ended December 31, 2015, 2014, and 2013, respectively, but did not increase taxable income. There were downward adjustments of pre-Privatization unpaid loss reserves, excluding the LPT, of $56.3 million, $13.1 million, and $27.2 million for the years ended December 31, 2015, 2014, and 2013, respectively.

The LPT Reserve Adjustments for the years ended December 31, 2015, 2014, and 2013 increased GAAP net income by $6.4 million, $31.1 million, and $19.0 million, respectively, but did not increase taxable income. The LPT Contingent Commission Adjustments increased net income by $2.6 million, $10.8 million, and $4.3 million during 2015, 2014, and 2013, respectively, but did not increase taxable income.

As of December 31, 2015 and 2014, the Company had no unrecognized tax benefits.

Tax years 2012 through 2015 are subject to full examination by the federal taxing authority.

The significant components of deferred income taxes, net, were as follows as of December 31:



	2015				2014
	Deferred Tax				Deferred Tax
	Assets		Liabilities		Assets		Liabilities
	(in millions)
Unrealized capital gains, net	$	—	$	45.0	$	—	$	57.6
Deferred policy acquisition costs	—		15.7		—		15.7
Intangible assets	—		3.0		—		3.2
Loss reserve discounting for tax reporting	56.3		—		56.7		—
Unearned premiums	20.9		—		20.9		—
Allowance for bad debt	4.3		—		2.7		—
Stock based compensation	4.1		—		5.8		—
Accrued liabilities	8.4		—		7.5		—
Minimum tax credit	28.0		—		19.6		—
Net operating loss carryforward	8.7		—		16.2		—
Other	8.4		7.5		2.5		5.7
Total	$	139.1	$	71.2	$	131.9	$	82.2
Deferred income taxes, net	$	67.9			$	49.7

At December 31, 2015, the Company had a $25.0 million net operating loss carry-forward. This is due to expire beginning 2032 through 2033. At December 31, 2015, the Company had a minimum tax credit of $28.0 million that may be carried forward indefinitely.

Deferred tax assets are required to be reduced by a valuation allowance if it is more likely than not that all or some portion of the deferred tax asset will not be realized. Realization of the deferred income tax asset is dependent on the Company generating sufficient taxable income in future years as the deferred income tax charges become currently deductible for tax reporting purposes. Although realization is not assured, management believes that it is more likely than not that the net deferred income tax asset will be realized.

Liability for Unpaid Losses and Loss Adjustment Expenses

12 Months Ended

Dec. 31, 2015

Liability for Unpaid Losses and Loss Adjustment Expenses [Abstract]

Liability for Unpaid Losses and Loss Adjustment Expenses

The following table represents a reconciliation of changes in the liability for unpaid losses and LAE.



	Years Ended December 31,
	2015			2014		2013
	(in millions)
Unpaid losses and LAE, gross of reinsurance, at beginning of period	$	2,369.7		$	2,330.5	$	2,231.5
Less reinsurance recoverable, excluding bad debt allowance, on unpaid losses and LAE	669.5			743.1		805.4
Net unpaid losses and LAE at beginning of period	1,700.2			1,587.4		1,426.1
Losses and LAE, net of reinsurance, incurred in:
Current year	456.9			503.8		494.5
Prior years	(7.2		)	4.6		7.0
Total net losses and LAE incurred during the period	449.7			508.4		501.5
Paid losses and LAE, net of reinsurance, related to:
Current year	75.4			75.9		78.5
Prior years	355.2			319.7		261.7
Total net paid losses and LAE during the period	430.6			395.6		340.2
Ending unpaid losses and LAE, net of reinsurance	1,719.3			1,700.2		1,587.4
Reinsurance recoverable, excluding bad debt allowance, on unpaid losses and LAE	628.2			669.5		743.1
Unpaid losses and LAE, gross of reinsurance, at end of period	$	2,347.5		$	2,369.7	$	2,330.5

Total net losses and LAE included in the above table excludes the impact of the amortization of the Deferred Gain and the LPT Reserve Adjustment (Note 10).

In 2015, the Company had $7.2 million of favorable prior accident year loss development, which included $9.0 million of favorable prior accident year loss development on its voluntary risk business, which was partially offset by $1.8 million of unfavorable loss development related to its assigned risk business. In 2014, the increase in the estimate of incurred losses and LAE attributable to insured events in prior years was primarily related to the Company's assigned risk business. In 2013, the increase in the estimate of incurred losses and LAE attributable to insured events in prior years included $5.0 million related to actual paid losses that were more than expected and the impact of new information on selected patterns of claims emergence and payments used in the projection of future loss payments and $1.9 million related to the Company's assigned risk business.

In California, where the Company's operations began on July 1, 2002, the actuaries' and management's initial expectations of ultimate losses and patterns of loss emergence and payment were based on benchmarks derived from analyses of historical insurance industry data in California. No historical data from the Company's California insurance subsidiary existed prior to July 1, 2002; however, some historical data was available for the prior years for some of the market segments the Company entered in California, but was limited as to the number of loss reserve evaluation points available. The industry-based benchmarks were judgmentally adjusted for the anticipated impact of significant environmental changes, specifically the enactment of major changes to the statutory workers' compensation benefit structure and the manner in which claims are administered and adjudicated in California. The actual emergence and payment of claims by the Company's California insurance subsidiary have been more favorable than those initial expectations through 2008, due in part to the enactment of the major changes in the California workers' compensation environment. The Company's recent loss experience, from 2010 through 2015, indicates an upward trend in medical costs that is reflected in our loss reserves; however, the Company's indemnity claims frequency (the number of claims expressed as a percentage of payroll) decreased year-over-year in 2015 and 2014. The Company's estimates assume that increasing medical cost trends will continue and will impact the Company's long-term claims costs and loss reserves.

The Company continues to develop its own loss experience in California and will rely more on its experience and less on historical industry data in projecting its reserve requirements as such data becomes available. As the actual experience of the Company emerges, it will continue to evaluate prior estimates, which may result in additional adjustments in reserves.

In Nevada, the Company has compiled a lengthy history of workers' compensation claims payment patterns based on the business of the Fund and EICN, but the emergence and payment of claims in recent years has been more favorable than in the long-term history in Nevada with the Fund. The expected patterns of claim payments and emergence used in the projection of the Company's ultimate claim payments are based on both the long and short-term historical paid data. In recent evaluations, claim patterns have continued to emerge in a manner consistent with short-term historical data. Consequently, for California and Nevada, the Company has relied more heavily on claim projection patterns observed in recent years.

Loss reserves shown in the consolidated balance sheets are net of $26.8 million and $25.1 million for anticipated subrogation recoveries as of December 31, 2015 and 2014, respectively.

Reinsurance

12 Months Ended

Dec. 31, 2015

Reinsurance [Abstract]

Reinsurance

The Company is involved in the cession and assumption of reinsurance with non-affiliated companies. Risks are reinsured with other companies on both a quota share and excess of loss basis.

Reinsurance transactions reflected in the accompanying consolidated statements of comprehensive income were as follows:



	Years Ended December 31,
	2015						2014						2013
	Written			Earned			Written			Earned			Written			Earned
	(in millions)
Direct premiums	$	684.9		$	686.0		$	686.8		$	684.3		$	680.5		$	645.4
Assumed premiums	12.8			12.8			10.9			10.3			9.4			8.3
Gross premiums	697.7			698.8			697.7			694.6			689.9			653.7
Ceded premiums	(8.4		)	(8.4		)	(10.1		)	(10.1		)	(11.4		)	(11.4		)
Net premiums	$	689.3		$	690.4		$	687.6		$	684.5		$	678.5		$	642.3
Ceded losses and LAE incurred	$	10.1					$	17.2					$	10.7

Ceded losses and LAE incurred includes the amortization of the Deferred Gain, LPT Reserve Adjustments, and LPT Contingent Commission Adjustments.

Excess of Loss Reinsurance

The Company has consistently maintained excess of loss reinsurance coverage to protect it against the impact of large and/or catastrophic losses in its workers' compensation business. The Company currently maintains reinsurance for losses from a single occurrence or catastrophic event in excess of $7.0 million and up to $200.0 million, subject to certain exclusions. The reinsurance coverage includes coverage for acts of terrorism, excluding nuclear, biological, chemical, and radiological events. Any liability outside the coverage limits of the reinsurance program is retained by the Company. The Company's current reinsurance program is effective July 1, 2015 through June 30, 2016. The Company's reinsurance programs covering older accident years have generally had similar terms.

LPT Agreement

Recoverables from reinsurers on unpaid losses and LAE amounted to $628.2 million and $669.5 million at December 31, 2015 and 2014, respectively. At each of December 31, 2015 and 2014, $498.0 million and $534.8 million, respectively, of those recoverables was related to the LPT Agreement that was entered into in 1999 by the Fund and assumed by EICN. Under the LPT Agreement, substantially all of the Fund's losses and LAE on claims incurred prior to July 1, 1995, have been ceded to three unaffiliated reinsurers on a 100% quota share basis. Investments have been placed in trust by the three reinsurers as security for payment of the reinsured claims. Under the LPT Agreement, initially $1.5 billion in liabilities for the incurred but unpaid losses and LAE related to claims incurred prior to July 1, 1995, were reinsured for consideration of $775.0 million. The LPT Agreement provides coverage up to $2.0 billion. Through December 31, 2015, the Company has paid losses and LAE claims totaling $695.2 million related to the LPT Agreement.

The Company amortized $11.4 million, $13.1 million, and $14.6 million of the Deferred Gain for the years ended December 31, 2015, 2014, and 2013, respectively. Additionally, the Deferred Gain was reduced by $6.4 million, $31.1 million and $19.0 million for the years ended December 31, 2015, 2014, and 2013, respectively, due to favorable LPT Reserve Adjustments and by $2.6 million, $10.8 million, and $4.3 million for the years ended December 31, 2015, 2014, and 2013, respectively, due to favorable LPT Contingent Commission Adjustments (Note 2).

- Definition

The entire disclosure pertaining to the existence, magnitude and information about insurance that has been ceded to or assumed from another insurance company, including the methodologies and assumptions used in determining recorded amounts.

+ References + Details

Notes Payable

12 Months Ended

Dec. 31, 2015

Notes Payable [Abstract]

Notes Payable

Notes payable is comprised of the following:



	December 31,
	2015		2014
	(in millions)
Credit facility, with variable interest, as described below	$	—	$	60.0
Dekania Surplus Note, due April 30, 2034 with variable interest of 425 basis points above 90-day LIBOR	10.0		10.0
ICONS Surplus Note, due May 26, 2034 with variable interest of 425 basis points above 90-day LIBOR	12.0		12.0
Alesco Surplus Note, due December 15, 2034 with variable interest of 405 basis points above 90-day LIBOR	10.0		10.0
Balance	$	32.0	$	92.0

On December 28, 2010, the Company entered into a credit facility, under which the Company was provided with: (a) $100.0 million line of credit through December 31, 2011; (b) $90.0 million line of credit from January 1, 2012 through December 31, 2012; (c) $80.0 million line of credit from January 1, 2013 through December 31, 2013; (d) $70.0 million line of credit from January 1, 2014 through December 31, 2014; and (e) $60.0 million line of credit from January 1, 2015 through December 31, 2015. Amounts outstanding bear interest at a rate equal to, at our option: (a) a fluctuating rate of 1.75% above prime rate or (b) a fixed rate that is 1.75% above the LIBOR rate then in effect. Interest paid during the years ended December 31, 2015, 2014, and 2013 totaled $1.3 million, $1.4 million, and $1.6 million, respectively. In accordance with the terms of the contract, the remaining principal balance of $60.0 million was repaid on the credit facility during the fourth quarter of 2015.

EPIC has a $10.0 million surplus note to Dekania CDO II, Ltd. issued as part of a pooled transaction. The note matures in 2034 and became callable by the Company in the second quarter of 2009. The terms of the note provide for quarterly interest payments at a rate 425 basis points in excess of the 90-day LIBOR. Both the payment of interest and repayment of the principal under this note and the surplus notes described in the succeeding two paragraphs are subject to the prior approval of the Florida Department of Financial Services. Interest paid during each of the years ended December 31, 2015, 2014, and 2013 was $0.5 million. Interest accrued as of December 31, 2015 and 2014 was $0.1 million.

EPIC has a $12.0 million surplus note to ICONS, Inc. issued as part of a pooled transaction. The note matures in 2034 and became callable by the Company in the second quarter of 2009. The terms of the note provide for quarterly interest payments at a rate 425 basis points in excess of the 90-day LIBOR. Interest paid during each of the years ended December 31, 2015, 2014, and 2013 was $0.6 million, $0.5 million and $0.6 million, respectively. Interest accrued as of December 31, 2015 and 2014 was $0.1 million.

EPIC has a $10.0 million surplus note to Alesco Preferred Funding V, LTD issued as part of a pooled transaction. The note matures in 2034 and became callable by the Company in the fourth quarter of 2009. The terms of the note provide for quarterly interest payments at a rate 405 basis points in excess of the 90-day LIBOR. Interest paid during each of the years ended December 31, 2015, 2014, and 2013 was $0.4 million. Interest accrued as of December 31, 2015 and 2014 was less than $0.1 million.

Principal payment obligations on notes payable outstanding at December 31, 2015, were as follows:



Year	Principal Due
	(in millions)
2016	$	—
2017	—
2018	—
2019	—
2020	—
Thereafter	32.0
Total	$	32.0

Commitments and Contingencies

12 Months Ended

Dec. 31, 2015

Commitments and Contingencies [Abstract]

Commitments and Contingencies Disclosure

Commitments and Contingencies

Leases

The Company leases office facilities and certain equipment under operating and capital leases. Most leases have renewal options, typically with increased rental rates during the option period. Certain of these leases contain options to purchase the property at amounts that approximate fair market value; other leases contain options to purchase at a bargain purchase price. At December 31, 2015, the remaining lease terms expire over the next six years.

The future lease payments for the next five years on these non-cancelable operating and capital leases at December 31, 2015, were as follows:



Year	Operating Leases		Capital Leases
	(in millions)
2016	$	4.9	$	0.3
2017	4.8		0.3
2018	3.5		0.2
2019	3.0		—
2020	2.6		—
Thereafter	1.1		—
Total	$	19.9	$	0.8

Included in the future minimum capital lease payments are future interest charges of $0.1 million. Facilities rent expense was $4.9 million, $4.8 million, and $5.0 million for the years ended December 31, 2015, 2014, and 2013, respectively.

Property held under capital leases is included in property and equipment as follows:



Asset Class	2015			2014
	(in millions)
Computers and software	$	0.4		$	0.9
Automobiles	1.2			1.2
	1.6			2.1
Accumulated amortization	(1.0		)	(1.0		)
Total	$	0.6		$	1.1

Contingencies Surrounding Insurance Assessments

All of the states where the Company's insurance subsidiaries are licensed to transact business require property and casualty insurers doing business within the respective state to pay various insurance assessments. The Company accrues a liability for estimated insurance assessments as direct premiums are written, losses are recorded, or as other events occur in accordance with various states' laws and regulations, and defers these costs and recognizes them as an expense as the related premiums are earned. The Company had an accrued liability for guaranty fund assessments, second injury funds assessments, and other insurance assessments totaling $22.0 million and $18.8 million as of December 31, 2015 and 2014, respectively. These liabilities are generally expected to be paid over one to eighty year periods based on individual state's regulations. The Company also recorded an asset of $21.4 million and $13.0 million, as of December 31, 2015 and 2014, respectively, for prepaid policy charges still to be collected in the future from policyholders, assessments that may be recovered through a reduction in future premium taxes in certain states, and for expected refunds of certain prepaid assessments based on a change in the Company's premium over time. These assets are expected to be realized over one to ten year periods in accordance with their type and individual state's regulations.

Stock-Based Compensation

12 Months Ended

Dec. 31, 2015

Stock-Based Compensation [Abstract]

Stock-Based Compensation

The Employers Holdings, Inc. Amended and Restated Equity and Incentive Plan (the Plan) is administered by the Compensation Committee of the Board of Directors, which is authorized to grant, at its discretion, awards to officers, employees, non-employee directors, consultants, and independent contractors. The maximum number of common shares reserved for grants of awards under the Plan was 7,105,838 shares, prior to reductions for grants made. The Plan provides for the grant of stock options (both incentive stock options and nonqualified stock options), stock appreciation rights, shares of restricted stock, restricted stock units (RSUs), performance stock units (PSUs), and other stock-based awards.

As of December 31, 2015, nonqualified stock options, RSUs, and PSUs have been granted, but no incentive stock options, stock appreciation rights, or shares of restricted stock have been granted under the Plan.

Compensation costs are recognized based on expected performance, if applicable, net of any estimated forfeitures on a straight-line basis over the employee requisite service periods. Forfeiture rates are based on historical experience and are adjusted in subsequent periods for differences in actual forfeitures from those estimated. Net stock-based compensation expense recognized in the accompanying consolidated statements of comprehensive income was as follows:



	Years Ended December 31,
	2015		2014		2013
Stock-based compensation expense related to:	(in millions)
Nonqualified stock options	$	1.0	$	1.2	$	1.7
RSUs	2.0		1.9		2.3
PSUs	1.6		2.9		1.6
Total	4.6		6.0		5.6
Less: related tax benefit	1.6		2.1		2.0
Net stock-based compensation expense	$	3.0	$	3.9	$	3.6

Nonqualified Stock Options

The fair value of the stock options granted is estimated using a Black-Scholes option pricing model that uses the assumptions noted in the following table. During the years ended December 31, 2015, 2014, and 2013, the expected stock price volatility used to value the options granted in 2015, 2014, and 2013 was based on the volatility of the Company's historical stock price since February 2007. The expected term of the options granted in 2015, 2014, and 2013 was calculated using the 'plain-vanilla' calculation provided in the guidance of the Securities and Exchange Commission's Staff Accounting Bulletin No. 107. The dividend yield was calculated using amounts authorized by the Board of Directors. The risk-free interest rate is the yield on the grant date of the options of U.S. Treasury zero coupon securities with a maturity comparable to the expected term of the options.

The Company anticipates issuing new shares upon exercise of stock options.

The fair value of the stock options granted during the years ended December 31, 2015, 2014, and 2013 was calculated using the following weighted average assumptions:



	2015		2014		2013
Expected volatility	38.0	%	39.0	%	40.1	%
Expected life (in years)	4.8		4.8		4.8
Dividend yield	1.0	%	1.2	%	1.1	%
Risk-free interest rate	1.6	%	1.6	%	0.8	%
Weighted average grant date fair values of options granted	$7.63		$6.66		$7.04

Changes in outstanding stock options for the year ended December 31, 2015 were as follows:



	Number of Options		Weighted-Average Exercise Price		Weighted Average Remaining Contractual Life
Options outstanding at December 31, 2012	1,830,772		$	16.97	3.7 years
Granted	162,800		22.24		6.2 years
Exercised	(411,295	)	17.89
Expired	(6,900	)	17.00
Forfeited	(28,479	)	18.90
Options outstanding at December 31, 2013	1,546,898		17.24		3.4 years
Granted	141,744		20.87		6.2 years
Exercised	(120,494	)	17.89
Expired	(2,400	)	17.00
Forfeited	(44,458	)	19.99
Options outstanding at December 31, 2014	1,521,290		17.45		2.9 years
Granted	80,800		24.20		6.2 years
Exercised	(463,466	)	16.43
Forfeited	(17,079	)	20.21
Options outstanding at December 31, 2015	1,121,545		18.31		2.8 years
Exercisable at December 31, 2015	849,312		17.28		2.1 years

At December 31, 2015, the Company had yet to recognize $1.4 million in deferred compensation related to nonqualified stock option grants and expects to recognize these costs on a straight-line basis over the next 39 months. The fair value of options vested and the intrinsic value of outstanding and exercisable options as of December 31, were as follows:



	2015		2014		2013
	(in millions)
Fair value of options vested	$	1.3	$	1.6	$	1.8
Intrinsic value of outstanding options	10.1		9.2		22.3
Intrinsic value of exercisable options	8.5		7.8		15.2

The intrinsic value of options exercised was $4.0 million, $0.5 million, and $3.7 million for the years ended December 31, 2015, 2014, and 2013.

RSUs

The Company has awarded RSUs to non-employee members of the Board of Directors and certain officers of the Company. The RSUs awarded to non-employee members of the Board of Directors generally vest on the first anniversary of the award date. RSU grants allow each non-employee Director to decide whether to defer settlement of the RSUs until six months after termination of Board service or settle the RSUs at vesting. Dividend equivalents are granted to Directors who elected to defer settlement of the RSUs after the grants vested. RSUs awarded to officers of the Company have a service vesting period of approximately four years from the date awarded and vest 25% on or after each of the subsequent four anniversaries of such date. These RSUs are subject to accelerated vesting in certain limited circumstances, such as: retirement, death or disability of the holder, or in connection with a change of control of the Company.

Changes in outstanding RSUs for the year ended December 31, 2015 were as follows:



	Number of RSUs		Weighted Average Grant Date Fair Value
RSUs outstanding at December 31, 2012	406,262		$	16.65
Granted	84,215		23.57
Forfeited	(10,924	)	18.85
Vested	(121,207	)	15.97
RSUs outstanding at December 31, 2013	358,346		18.44
Granted	87,396		21.02
Forfeited	(16,690	)	20.18
Vested	(122,185	)	18.26
RSUs outstanding at December 31, 2014	306,867		19.15
Granted	112,048		24.19
Forfeited	(7,749	)	20.99
Vested	(92,133	)	19.74
RSUs outstanding at December 31, 2015	319,033		20.71
Vested but unsettled RSUs at December 31, 2015	124,149		17.73

At December 31, 2015, the Company had yet to recognize $3.2 million in deferred compensation related to RSU grants and expects to recognize these costs on a straight-line basis over the next 39 months. The grant date fair value of RSUs vested and the intrinsic value of vested RSUs for the years ended December 31, were as follows:



	2015		2014		2013
	(in millions)
Grant date fair value of RSUs vested	$	1.7	$	2.2	$	1.9
Intrinsic value of vested RSUs	2.2		2.7		2.9

The intrinsic value of outstanding RSUs was $8.7 million, $7.2 million, and $11.3 million at December 31, 2015, 2014, and 2013.

PSUs

The Company awarded PSUs to certain officers of the Company as follows:



Date of Grant	Target Number Awarded	Fair Value on Date of Grant		Aggregate Fair Value on Date of Grant
				(in millions)
March 2013⁽¹⁾	147,440	$	22.24	$	3.3
March 2014⁽¹⁾	125,340	20.87		2.6
March 2015⁽²⁾	110,000	24.20		2.7


(1)	The PSUs granted in 2013 and 2014 have a performance period of three years and are subject to certain performance goals, based on the Company's statutory combined ratio, with payouts that range from 0% to 200% of the target awards. The ultimate payout of the PSUs awarded in 2013 was 0% of the target award.


(2)	The PSUs awarded in March 2015 were awarded to certain officers of the Company and have a performance period of two years followed by an additional one year vesting period. The PSU awards are subject to certain performance goals with payouts that range from 0% to 200% of the target awards. The value shown in the table represents the aggregate number of PSUs awarded at the target level.

At December 31, 2015, the Company had yet to recognize $4.4 million in deferred compensation related to PSU grants and expects to recognize these costs on a straight-line basis over the next 24 months. This is based on the expectation of the Company achieving a 80% target rate for the 2014 PSUs and 200% for the 2015 PSUs.

Statutory Matters

12 Months Ended

Dec. 31, 2015

Stautory Matters [Abstract]

Statutory Financial Data Disclosure

Statutory Matters

Statutory Financial Data

The combined capital stock, surplus, and net income of the Company's insurance subsidiaries (EICN, ECIC, EPIC, and EAC), prepared in accordance with the statutory accounting practices (SAP) of the National Association of Insurance Commissioners (NAIC) as well as SAP permitted by the states of California, Florida, and Nevada, were as follows:



	December 31,
	2015		2014
	(in millions)
Capital stock and unassigned surplus	$	498.8	$	413.8
Paid in capital	174.9		174.9
Surplus notes	32.0		32.0
Total statutory surplus	$	705.7	$	620.7

Net income for the Company's insurance subsidiaries prepared in accordance with SAP for the years ended December 31, 2015, 2014 and 2013 was $87.8 million, $58.6 million and $19.3 million, respectively.

Treatment of the LPT Agreement, deferred policy acquisition costs, fair value of financial instruments, and the surplus notes (see Notes 5, 10, and 11) are the primary differences in the SAP-basis capital stock and total surplus of the insurance subsidiaries of $705.7 million and $620.7 million, and the GAAP-basis equity of the Company of $760.8 million and $686.8 million as of December 31, 2015 and 2014, respectively. Under SAP accounting, the retroactive reinsurance gain resulting from the LPT Agreement is recorded as a special component of surplus (special surplus funds) in the initial year of the contract, and not reported as unassigned surplus until the Company has recovered amounts in excess of the original consideration paid. The special surplus funds are also reduced by the amount of extraordinary dividends as approved by the Nevada Division of Insurance. Under SAP, the surplus notes are recorded as a separate component of surplus. Under SAP, changes to the estimated contingent profit commission under the LPT Agreement are reflected in commission expense in the period that the estimate is revised.

Insurance Company Dividends

The ability of EHI to pay dividends on the Company's common stock and to pay other expenses will be dependent to a significant extent upon the ability of the Nevada domiciled insurance company, EICN, and the Florida domiciled insurance company, EPIC, to pay dividends to their immediate holding company, Employers Group, Inc. (EGI) and, in turn, the ability of EGI to pay dividends to EHI. ECIC and EAC have the ability to declare and pay dividends to EICN and EPIC, respectively, subject to certain restrictions. The amount of dividends each of the Company's subsidiaries may pay to their immediate parent is limited by the laws of its respective state of domicile.

Nevada law limits the payment of cash dividends by EICN to its parent by providing that payments cannot be made except from available and accumulated surplus, otherwise unrestricted (unassigned), and derived from realized net operating profits and realized and unrealized capital gains. A stock dividend may be paid out of any available surplus. A cash or stock dividend prohibited by these restrictions may only be declared and distributed as an extraordinary dividend upon the prior approval of the Nevada Commissioner of Insurance (Nevada Commissioner). EICN may not pay such an extraordinary dividend or make an extraordinary distribution until the Nevada Commissioner either approves or does not disapprove the payment within 30 days after receiving notice of its declaration. An extraordinary dividend or distribution is defined by statute to include any dividend or distribution of cash or property whose fair market value, together with that of other dividends or distributions made within the preceding 12 months, exceeds the greater of: (a) 10% of EICN's statutory surplus as regards to policyholders at the next preceding December 31; or (b) EICN's statutory net income, not including realized capital gains, for the 12-month period ending at the next preceding December 31. As of December 31, 2015, EICN had positive unassigned surplus of $423.1 million. During 2015, EICN did not pay any dividends. The maximum dividends that may be paid in 2016 by EICN without prior approval is $49.7 million.

Under Florida law, without regulatory approval, EPIC may pay dividends if they do not exceed the greater of: the lesser of 10% of surplus or net income, not including realized capital gains, plus a 2-year carry forward; 10% of surplus, with dividends payable limited to unassigned funds minus 25% of unrealized capital gains; or, the lesser of 10% of surplus or net investment income plus a 3-year carry forward with dividends payable limited to unassigned funds minus 25% of unrealized capital gains. During 2015, EPIC did not pay any dividends. The maximum dividends that may be paid in 2016 by EPIC without prior approval is $28.1 million.

Regulatory Requirements and Restrictions

ECIC is subject to regulation by the California Department of Insurance (California DOI). The ability of ECIC to pay dividends was further limited by restrictions imposed by the California DOI in its approval of the Company's October 1, 2008 reinsurance pooling agreement. Under that approval: (a) ECIC must initiate discussions of its business plan with the California DOI if its net written premium to policyholder surplus ratio exceeds 1.5 to 1; (b) ECIC will not exceed a ratio of net written premium to policyholder surplus of 2 to 1 without approval of the California DOI; (c) if at any time ECIC's policyholder surplus decreases to 80% or less than the September 30, 2008 balance, ECIC shall cease issuing new policies in California, but may continue to renew existing policies until it has (i) received a capital infusion to bring its surplus position to the same level as that as of September 30, 2008 and (ii) submitted a new business plan to the California DOI; (d) ECIC will maintain a risk based capital (RBC) level of at least 350% of the authorized control level; (e) should ECIC fail to comply with any commitments listed herein, ECIC will consent to any request by the California DOI to cease issuing new policies in California, but may continue to renew existing policies until such time that as ECIC is able to achieve full compliance with each commitment; and (f) the obligations listed shall only terminate with the written consent of the California DOI. During the years ended December 31, 2015, 2014, and 2013, ECIC was in compliance with these requirements.

EPIC and EAC are subject to regulation by the Florida Department of Financial Services (FDFS). Florida statute Section 624.408 requires EPIC and EAC to maintain minimum capital and surplus of the greater of $4.0 million or 10% of total liabilities. Florida statute Section 624.4095 requires EPIC and EAC to maintain a ratio of written premiums times 1.25 to surplus of no greater than 10-to-1 for gross written premiums and 4-to-1 for net written premiums. During the years ended December 31, 2015, 2014, and 2013, EPIC and EAC were in compliance with these statutes.

Additionally, EICN, ECIC, EPIC, and EAC are required to comply with NAIC RBC requirements. RBC is a method of measuring the amount of capital appropriate for an insurance company to support its overall business operations in light of its size and risk profile. NAIC RBC standards are used by regulators to determine appropriate regulatory actions relating to insurers that show signs of weak or deteriorating conditions. As of December 31, 2015, 2014, and 2013, EICN, ECIC, EPIC, and EAC each had total adjusted capital above all regulatory action levels.

Accumulated Other Comprehensive Income, Net

12 Months Ended

Dec. 31, 2015

Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]

Accumulated Other Comprehensive Income, Net

Accumulated other comprehensive income, net, is comprised of unrealized gains on investments classified as available-for-sale, net of deferred tax expense. The following table summarizes the components of accumulated other comprehensive income, net:



	Years Ended December 31,
	2015			2014
	(in millions)
Net unrealized gain on investments, before taxes	$	128.6		$	164.5
Deferred tax expense on net unrealized gains	(45.0		)	(57.6		)
Total accumulated other comprehensive income, net	$	83.6		$	106.9

- Definition

The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e689-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Topic 220
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 505
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-Paragraph 1
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Paragraph 11
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Reclassification Adjustments
-URI http://asc.fasb.org/extlink&oid=6522872

+ Details

Employee Benefit and Retirement Plans	12 Months Ended
Employee Benefit and Retirement Plans	Dec. 31, 2015
Employee Benefit and Retirement Plans [Abstract]
Compensation and Employee Benefit Plans	Employee Benefit and Retirement Plans The Company maintains a 401(k) defined contribution plan covering all eligible Company employees (the Employers 401(k) Plan). Under the Employers 401(k) Plan, the Company's safe harbor matching consists of 100% matching contribution on salary deferrals up to 3% of compensation and then 50% matching contribution on salary deferrals from 3% to 5% of compensation. The Company's contribution to the Employers 401(k) Plan was $1.8 million, $1.7 million, and $1.2 million for the years ended December 31, 2015, 2014, and 2013, respectively.

Earnings Per Share

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Earnings Per Share

Basic earnings per share includes no dilution and is computed by dividing income applicable to stockholders by the weighted average number of shares outstanding for the period. Diluted earnings per share reflect the potential dilutive impact of all convertible securities on earnings per share. Diluted earnings per share includes shares assumed issued under the “treasury stock method,” which reflects the potential dilution that would occur if outstanding RSUs and PSUs vested, and options were to be exercised.

The following table presents the net income and the weighted average shares outstanding used in the earnings per share common share calculations.



	Years Ended December 31,
	2015		2014		2013
	(in millions, except share data)
Net income available to stockholders–basic and diluted	$	94.4	$	100.7	$	63.8
Weighted average number of shares outstanding–basic	32,070,911		31,529,621		31,142,534
Effect of dilutive securities:
Stock options	286,764		223,811		464,334
PSUs	155,768		264,511		177,040
RSUs	48,010		51,126		154,259
Dilutive potential shares	490,542		539,448		795,633
Weighted average number of shares outstanding–diluted	32,561,453		32,069,069		31,938,167

Diluted earnings per share excludes outstanding options and other common stock equivalents in periods where the inclusion of such options and common stock equivalents would be anti-dilutive. The following table presents options, PSUs and RSUs that were excluded from diluted earnings per share.



	Years Ended December 31,
	2015	2014	2013
Options excluded as the exercise price was greater than the average market price	20,200	173,247	—
Options, PSUs and RSUs excluded under the treasury method, as the potential proceeds on settlement or exercise was greater than the value of shares acquired	257,405	260,171	162,800

Selected Quarterly Financial Data

12 Months Ended

Dec. 31, 2015

Selecled Quarterly Financial Data (Unaudited) [Abstract]

Quarterly Financial Information

Selected Quarterly Financial Data (Unaudited)

Quarterly results for the years ended December 31, 2015 and 2014 were as follows:



	2015 Quarters Ended
	March 31		June 30		September 30		December 31
	(in millions, except per share data)
Net premiums earned	$	159.0	$	170.6	$	179.0	$	181.8
Net realized gains (losses) on investments	1.2		1.9		2.0		(15.8		)
Losses and loss adjustment expenses	106.2		101.5		115.8		105.9
Commission expense	18.7		22.9		21.0		22.8
Underwriting and other operating expenses	33.5		32.5		31.6		37.6
Income tax expense (benefit)	4.1		4.1		5.9		(9.1		)
Net income	14.0		29.2		24.5		26.7
Earnings per common share:
Basic	0.44		0.91		0.76		0.83
Diluted	0.43		0.90		0.75		0.82



	2014 Quarters Ended
	March 31		June 30		September 30		December 31
	(in millions, except per share data)
Net premiums earned	$	167.2	$	172.6	$	172.1	$	172.6
Net realized gains on investments	3.3		9.2		1.8		2.0
Losses and loss adjustment expenses	122.3		98.5		122.4		110.2
Commission expense	20.0		20.4		20.6		20.4
Underwriting and other operating expenses	33.3		33.1		31.9		30.9
Income tax expense	1.3		2.0		1.3		1.3
Net income	10.8		45.6		15.2		29.1
Earnings per common share:
Basic	0.34		1.45		0.48		0.92
Diluted	0.34		1.42		0.47		0.91

Fourth Quarter Adjustments

The fourth quarter of 2015 was impacted by two changes in estimates: (1) favorable prior accident year loss development of $8.5 million, which included $9.0 million of favorable prior accident year loss development on the Company's voluntary risk business, partially offset by $0.5 million of unfavorable loss development related to assigned risk business, that increased net income by $8.5 million or $0.26 per basic and diluted share; and (2) a $36.9 million reallocation of reserves from non-taxable periods prior to January 1, 2000 to taxable years, which reduced our effective tax rate by 65.3 percentage points, resulting in an increase to net income of $11.5 million, or $0.36 and $0.35 per basic and diluted share, respectively.

The fourth quarter of 2014 was impacted by two changes in estimates, including: (1) a favorable LPT Reserve Adjustment, which reduced the Company's losses and LAE by $8.8 million, and increased net income by $8.8 million, or $0.28 and $0.27 per basic and diluted share, respectively; and (2) an LPT Contingent Commission Adjustment, which reduced the Company's losses and LAE by $2.9 million, resulting in an increase to net income of $2.9 million, or $0.09 per basic and diluted share. See Note 2.

Schedule II. Condensed Financial Information of Registrant

12 Months Ended

Dec. 31, 2015

Notes to Condensed Financial Statments [Abstract]

Schedule II. Condensed Financial Information of Registrant



Employers Holdings, Inc.

Condensed Balance Sheets

	December 31,
	2015			2014
	(in thousands, except share data)
Assets
Investments:
Investment in subsidiaries	$	647,100		$	567,100
Investment in fixed maturity securities available-for-sale (amortized cost $40,200 in 2015 and $83,300 in 2014)	42,200			86,700
Equity securities at fair value (amortized cost $46,000 in 2015 and $48,600 in 2014)	51,600			58,600
Total investments	740,900			712,400

Cash and cash equivalents	1,400			10,900
Restricted cash and cash equivalents	—			4,600
Intercompany receivable	200			300
Federal income taxes receivable	1,700			6,600
Deferred income taxes, net	20,600			13,900
Other assets	1,500			1,900
Total assets	$	766,300		$	750,600

Liabilities and stockholders' equity
Accounts payable and accrued expenses	$	5,200		$	3,800
Notes payable	—			60,000
Other liabilities	300			—
Total liabilities	5,500			63,800

Stockholders' equity:
Common stock, $0.01 par value; 150,000,000 shares authorized 55,589,454 and 54,866,802 shares issued and 32,216,480 and 31,493,828 shares outstanding at December 31, 2015 and 2014, respectively	600			600
Preferred stock, $0.01 par value; 25,000,000 shares authorized non-issued	—			—
Additional paid-in capital	357,200			346,600
Retained earnings	682,000			595,300
Accumulated other comprehensive income, net	83,600			106,900
Treasury stock, at cost (23,372,974 shares at December 31, 2015 and 2014)	(362,600		)	(362,600		)
Total stockholders' equity	760,800			686,800
Total liabilities and stockholders' equity	$	766,300		$	750,600

See accompanying notes.



Employers Holdings, Inc.

Condensed Statements of Income

	Years Ended December 31,
	2015			2014			2013
	(in thousands, except per share data)
Revenues
Net investment income	$	4,000		$	5,200		$	6,000
Realized gains on investments	2,400			5,800			4,300
Total revenues	6,400			11,000			10,300

Expenses
Other operating expenses	13,800			13,500			12,000
Interest expense	1,100			1,400			1,600
Total expenses	14,900			14,900			13,600

Loss before income taxes and equity in earnings of subsidiary	(8,500		)	(3,900		)	(3,300		)
Income tax benefit	(3,300		)	(2,600		)	(1,500		)
Net loss before equity in earnings of subsidiary	(5,200		)	(1,300		)	(1,800		)
Equity in net income of subsidiary	99,600			102,000			65,600
Net income	$	94,400		$	100,700		$	63,800

Earnings per common share for the stated periods (Note 18):
Basic	$	2.94		$	3.19		$	2.05
Diluted	$	2.90		$	3.14		$	2.00

Cash dividends declared per common share	$	0.24		$	0.24		$	0.24

See accompanying notes.



Employers Holdings, Inc.

Condensed Statement of Cash Flows

	Years Ended December 31,
	2015			2014			2013
	(in thousands)
Operating activities
Net income	$	94,400		$	100,700		$	63,800
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Equity in net income of subsidiary	(99,600		)	(102,000		)	(65,600		)
Realized gains on investments	(2,400		)	(5,800		)	(4,300		)
Stock-based compensation	4,600			6,000			5,600
Excess tax benefits from stock-based compensation	(1,200		)	(1,200		)	—
Amortization of premium or investments, net	900			1,000			1,300
Deferred income tax expense	(4,600		)	(2,300		)	(500		)
Change in operating assets and liabilities:
Accounts payable and accrued expenses and other liabilities	1,700			1,200			(1,700		)
Federal income taxes	4,900			800			(1,800		)
Other assets	400			900			200
Intercompany payable/receivable	100			(1,400		)	5,600
Other	1,200			1,000			—
Net cash provided by (used in) operating activities	400			(1,100		)	2,600

Investing activities
Purchase of fixed maturity securities	(21,600		)	(12,000		)	(29,500		)
Purchase of equity securities	(19,000		)	(20,700		)	(23,600		)
Proceeds from sale of fixed maturity securities	18,300			4,100			35,500
Proceeds from maturities and redemptions of investments	45,500			32,600			17,600
Proceeds from sale of equity securities	24,000			20,600			15,500
Cash dividends received from subsidiary	—			—			3,600
Capital contributions to subsidiary	—			—			(44,000		)
Change in restricted cash equivalents	4,600			(4,100		)	(400		)
Net cash provided by (used in) investing activities	51,800			20,500			(25,300		)

Financing activities
Cash transactions related to stock-based compensation	4,800			1,500			6,500
Dividends paid to stockholders	(7,700		)	(7,600		)	(7,500		)
Payments on notes payable	(60,000		)	(10,000		)	(10,000		)
Excess tax benefits from stock-based compensation	1,200			1,200			—
Net cash used in financing activities	(61,700		)	(14,900		)	(11,000		)

Net increase (decrease) in cash and cash equivalents	(9,500		)	4,500			(33,700		)
Cash and cash equivalents at the beginning of the period	10,900			6,400			40,100
Cash and cash equivalents at the end of the period	$	1,400		$	10,900		$	6,400

See accompanying notes.

1. Nature of Operations and Summary of Significant Accounting Policies

Operations and Basis of Presentation

Employers Holdings, Inc. (EHI) is a Nevada holding company. Through its wholly owned insurance subsidiaries, Employers Insurance Company of Nevada (EICN), Employers Compensation Insurance Company (ECIC), Employers Preferred Insurance Company (EPIC), and Employers Assurance Company (EAC), EHI is engaged in the commercial property and casualty insurance industry, specializing in workers' compensation products and services. Unless otherwise indicated, all references to the “Company” refer to EHI, together with its subsidiaries.

EHI prepares its condensed financial statements in accordance with U.S. generally accepted accounting principles (GAAP), using the equity method. Under the equity method, the investment in subsidiary is stated at cost plus equity in earnings of its subsidiary. EHI receives dividends from its insurance subsidiaries in the form of cash and securities. The book value for these securities is stated at the fair market value at the date of transfer. These condensed financial statements should be read in conjunction with EHI's consolidated financial statements included elsewhere in this Annual Report on Form 10-K.

Estimates and Assumptions

The preparation of the financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expenses during the reporting period. As a result, actual results could differ from these estimates.

2. Income Taxes

EHI files a consolidated federal income tax return with its subsidiaries and has a tax allocation agreement with its subsidiaries. The equity in the undistributed earnings of subsidiaries included in the accompanying condensed statements of income is net of income taxes.

3. Investments



	Amortized Cost		Estimated Fair Value
	(in millions)
Due in one year or less	$	14.6	$	14.9
Due after one year through five years	15.6		16.1
Due after five years through ten years	3.3		3.7
Due after ten years	6.7		7.5
Total	$	40.2	$	42.2

At December 31, 2015, the fixed maturity securities had unrealized gains of $2.0 million which are included in accumulated comprehensive income, net in the accompanying condensed balance sheets.

During 2015, EHI purchased equity securities and utilized market quotations to determine their fair values.

4. Notes Payable

On December 28, 2010, EHI entered into a credit facility. See Note 11 of the Consolidated Financial Statements of Employers Holdings, Inc. and Subsidiaries included herein for a description of the terms of the Amended Credit Facility. Interest paid during the years ended December 31, 2015, 2014, and 2013 totaled $1.3 million, $1.4 million, and $1.6 million, respectively. In accordance with the terms of the contract, the remaining principal balance of $60.0 million was repaid on the credit facility during the fourth quarter of 2015.

5. Stock-Based Compensation

During 2015, EHI awarded 80,800 non-qualified stock options to officers, 112,048 RSUs to non-employee Directors and officers, and 110,000 PSUs to officers. During 2014, EHI awarded 141,744 non-qualified stock options to officers, 87,396 RSUs to non-employee Directors and officers, and 125,340 PSUs to officers. See Note 14 of the Consolidated Financial Statements of Employers Holdings, Inc. and Subsidiaries included herein for a detailed description of the stock-based compensation.

Schedule VI. Supplemental Information

12 Months Ended

Dec. 31, 2015

Supplemental Information for Property, Casualty Insurance Underwriters [Abstract]

Schedule of Supplemental Information for Property, Casualty Insurance Underwriters



Schedule VI. Supplemental Information Concerning Property - Casualty Insurance Operations

Employers Holdings, Inc. and Subsidiaries
Consolidated Supplemental Information Concerning Property and Casualty Insurance Operations

Year Ended	Deferred Policy Acquisition Costs		Reserves For Unpaid Losses And LAE		Unearned Premiums		Net Premiums Earned		Net Investment Income		Losses and LAE Related to Current Years		Losses and LAE Related to Prior Years (including LPT Amortization and Adj)			Amortization of Deferred Policy Acquisition Costs		Paid Losses And LAE (including LPT Amortization and Adj)		Net Premiums Written
(in millions)
2015	$	44.3	$	2,347.5	$	308.9	$	690.4	$	72.2	$	456.9	$	(27.6	)	$	103.9	$	410.2	$	689.3
2014	44.6		2,369.7		310.8		684.5		72.4		503.8		(50.5		)	102.7		340.6		687.6
2013	43.5		2,330.5		304.0		642.3		70.8		494.5		(31.0		)	96.9		302.3		678.5

Subsequent Events (Notes)	12 Months Ended
Subsequent Events (Notes)	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Events [Text Block]	Subsequent Events Each of the Company's insurance subsidiaries, EICN, ECIC, EPIC, and EAC, became a member of the Federal Home Loan Bank of San Francisco (FHLB) in January 2016. Membership allows each subsidiary access to collateralized advances, which may be used to support and enhance liquidity management. The amount of advances that may be taken are dependent on statutory admitted assets on a per company basis. Currently, none of the Company's subsidiaries has advances outstanding under the FHLB facility. On February 16, 2016, the Board of Directors authorized a share repurchase program for up to $50.0 million of the Company's common stock from February 22, 2016 through February 22, 2018 (the 2016 Program). The Company expects that shares of common stock may be purchased at prevailing market prices through a variety of methods, including open market or private transactions, in accordance with applicable laws and regulations and as determined by management. The timing and actual number of shares repurchased will depend on a variety of factors, including the share price, corporate and regulatory requirements, and other market and economic conditions. Repurchases under the 2016 Program may be commenced, modified, or suspended from time-to-time without prior notice.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2015

Summary of Significant Accounting Policies [Abstract]

Cash and Cash Equivalents, Policy

Cash and Cash Equivalents

The Company considers all highly liquid investments with an initial maturity of three months or less at the date of purchase to be cash equivalents.

Restricted Cash and Cash Equivalents, Policy

Restricted Cash and Cash Equivalents

Investments, Policy

Investments

Realized capital gains and losses on investments are determined on a specific-identification basis.

Revenue Recognition, Policy

Revenue Recognition

Deferred Policy Acquisition Costs, Policy

Deferred Policy Acquisition Costs

Unpaid Loss and LAE Reserves, Policy

Unpaid Loss and LAE Reserves

Reinsurance, Policy

Reinsurance

Ceded losses and LAE are accounted for on a basis consistent with those used in accounting for the original policies issued and the terms of the relevant reinsurance agreement.

Property, and Equipment, Policy

Property and Equipment

Property and equipment are stated at cost less accumulated depreciation (see Note 7). Expenditures for maintenance and repairs are charged against operations as incurred.

Obligations Held Under Capital Leases, Policy

Obligations Held Under Capital Leases

Income Taxes, Policy

Income Taxes

Credit Risk, Policy

Credit Risk

Fair Value of Financial Instruments, Policy

Fair Value of Financial Instruments

Goodwill and Other Intangible Assets, Policy

Goodwill and Other Intangible Assets

The gross carrying value, accumulated amortization, and net carrying value for the Company's intangible assets, by major class, as of December 31, were as follows:



	2015							2014
	Gross Carrying Value		Accumulated Amortization			Net Carrying Value		Gross Carrying Value		Accumulated Amortization			Net Carrying Value
	(in millions)
State licenses	$	7.7	$	—		$	7.7	$	7.7	$	—		$	7.7
Insurance relationships	9.4		$	(8.6	)	0.8		9.4		$	(8.1	)	1.3
Total	$	17.1	$	(8.6	)	$	8.5	$	17.1	$	(8.1	)	$	9.0



Year	Amount
	(in millions)
2016	0.4
2017	0.3
2018	0.1
Total	$	0.8

Stock-based Compensation, Policy

Stock-Based Compensation

Changes in Estimates (Tables)

12 Months Ended

Dec. 31, 2015

Changes in Estimates [Abstract]

Change to Contingent Profit Commission [Table Text Block]



	2015			2014			2013
	(in millions, except per share data)
Cumulative adjustment to the deferred reinsurance gain - LPT Agreement (Deferred Gain)⁽¹⁾	$	(2.6	)	$	(10.8	)	$	(4.3	)
Net income impact of change in estimate	2.6			10.8			4.3
EPS impact of change in estimate
Basic	0.08			0.34			0.14
Diluted	0.08			0.34			0.13


(1)	The cumulative adjustments to the Deferred Gain were also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, so that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.

Change Due to Estimated Reserves Ceded Under the LPT Agreement [Table Text Block]



	2015			2014			2013
	(in millions, except per share data)
Change in estimated reserves ceded under the LPT Agreement	$	(10.0	)	$	(46.8	)	$	(27.5	)
Cumulative adjustment to the Deferred Gain⁽¹⁾	(6.4		)	(31.1		)	(19.0		)
Net income impact of change in estimate	6.4			31.1			19.0
EPS impact of change in estimate
Basic	0.20			0.99			0.61
Diluted	0.20			0.97			0.59


(1)	The cumulative adjustments to the Deferred Gain were also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, so that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.

Change in Reserves for Non-taxable Periods [Table Text Block]



	2015			2014			2013
	(in millions, except per share data)
Reserves reallocated to taxable years	$	56.3		$	13.1		$	27.2
Impact to effective tax rate	(15.4		)%	(3.4		)%	(13.9		)%
Net income impact of change in estimate	$	15.3		$	3.6		$	7.4
EPS impact of change in estimate
Basic	0.48			0.11			0.24
Diluted	0.47			0.11			0.23

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2015

Summary of Significant Accounting Policies [Abstract]

Schedule of intangible assets table

The gross carrying value, accumulated amortization, and net carrying value for the Company's intangible assets, by major class, as of December 31, were as follows:



	2015							2014
	Gross Carrying Value		Accumulated Amortization			Net Carrying Value		Gross Carrying Value		Accumulated Amortization			Net Carrying Value
	(in millions)
State licenses	$	7.7	$	—		$	7.7	$	7.7	$	—		$	7.7
Insurance relationships	9.4		$	(8.6	)	0.8		9.4		$	(8.1	)	1.3
Total	$	17.1	$	(8.6	)	$	8.5	$	17.1	$	(8.1	)	$	9.0

Expected amortization expense table

Amortization expense is expected to be as follows:



Year	Amount
	(in millions)
2016	0.4
2017	0.3
2018	0.1
Total	$	0.8

Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2015

Fair Value of Financial Instruments [Abstract]

Estimated fair value of financial instruments table

The carrying value and the estimated fair value of the Company's financial instruments as of December 31, were as follows:



	2015				2014
	Carrying Value		Estimated Fair Value		Carrying Value		Estimated Fair Value
Financial assets	(in millions)
Investments (Note 6)	$	2,487.2	$	2,487.2	$	2,448.4	$	2,448.4
Cash and cash equivalents	56.6		56.6		103.6		103.6
Restricted cash and cash equivalents	2.5		2.5		10.8		10.8
Financial liabilities
Notes payable (Note 11)	$	32.0	$	36.6	$	92.0	$	97.8

Fair value, assets and liabilities measured on recurring basis table

The following table presents the items in the accompanying consolidated balance sheets that are stated at fair value and the corresponding fair value measurements.



	December 31, 2015						December 31, 2014
	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
	(in millions)
Fixed maturity securities
U.S. Treasuries	$	—	$	120.2	$	—	$	—	$	166.7	$	—
U.S. Agencies	—		24.4		—		—		39.6		—
States and municipalities	—		854.5		—		—		745.8		—
Corporate securities	—		925.3		—		—		908.3		—
Residential mortgage-backed securities	—		237.9		—		—		288.4		—
Commercial mortgage-backed securities	—		80.3		—		—		65.4		—
Asset-backed securities	—		45.9		—		—		61.5		—
Total fixed maturity securities	$	—	$	2,288.5	$	—	$	—	$	2,275.7	$	—
Equity securities	$	198.7	$	—	$	—	$	172.7	$	—	$	—

Investments (Tables)

12 Months Ended

Dec. 31, 2015

Investments [Abstract]

Available-for-sale securities table

The cost or amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the Company’s investments were as follows:



	Cost or Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
At December 31, 2015	(in millions)
Fixed maturity securities
U.S. Treasuries	$	116.4	$	3.9	$	(0.1	)	$	120.2
U.S. Agencies	23.0		1.4		—			24.4
States and municipalities	809.4		45.1		—			854.5
Corporate securities	913.4		19.9		(8.0		)	925.3
Residential mortgage-backed securities	231.8		7.1		(1.0		)	237.9
Commercial mortgage-backed securities	81.1		0.2		(1.0		)	80.3
Asset-backed securities	46.0		—		(0.1		)	45.9
Total fixed maturity securities	2,221.1		77.6		(10.2		)	2,288.5
Equity securities	137.5		65.8		(4.6		)	198.7
Total investments	$	2,358.6	$	143.4	$	(14.8	)	$	2,487.2

At December 31, 2014
Fixed maturity securities
U.S. Treasuries	$	160.9	$	5.8	$	—		$	166.7
U.S. Agencies	37.2		2.4		—			39.6
States and municipalities	701.6		44.4		(0.2		)	745.8
Corporate securities	880.7		30.8		(3.2		)	908.3
Residential mortgage-backed securities	278.6		10.6		(0.8		)	288.4
Commercial mortgage-backed securities	65.5		0.5		(0.6		)	65.4
Asset-backed securities	61.6		—		(0.1		)	61.5
Total fixed maturity securities	2,186.1		94.5		(4.9		)	2,275.7
Equity securities	97.8		75.5		(0.6		)	172.7
Total investments	$	2,283.9	$	170.0	$	(5.5	)	$	2,448.4

Investments classified by contractual maturity date table



	Amortized Cost		Estimated Fair Value
	(in millions)
Due in one year or less	$	113.6	$	115.1
Due after one year through five years	859.3		884.5
Due after five years through ten years	636.9		657.1
Due after ten years	252.4		267.7
Mortgage and asset-backed securities	358.9		364.1
Total	$	2,221.1	$	2,288.5



	Amortized Cost		Estimated Fair Value
	(in millions)
Due in one year or less	$	14.6	$	14.9
Due after one year through five years	15.6		16.1
Due after five years through ten years	3.3		3.7
Due after ten years	6.7		7.5
Total	$	40.2	$	42.2

Unrealized loss on investments table



	December 31, 2015						December 31, 2014
	Estimated Fair Value		Gross Unrealized Losses			Number of Issues	Estimated Fair Value		Gross Unrealized Losses			Number of Issues
Less than 12 months:	(dollars in millions)
Fixed maturity securities
U.S. Treasuries	$	27.4	$	(0.1	)	20	$	—	$	—		—
States and municipalities	—		—			—	20.6		(0.2		)	5
Corporate securities	328.4		(4.7		)	122	109.9		(0.8		)	42
Residential mortgage-backed securities	50.5		(0.8		)	24	—		—			—
Commercial mortgage-backed securities	51.5		(1.0		)	22	—		—			—
Asset-backed securities	34.1		—			27	—		—			—
Total fixed maturity securities	491.9		(6.6		)	215	130.5		(1.0		)	47
Equity securities	35.8		(4.6		)	45	10.1		(0.6		)	15
Total less than 12 months	$	527.7	$	(11.2	)	260	$	140.6	$	(1.6	)	62

Greater than 12 months:
Fixed maturity securities
Corporate securities	$	34.6	$	(3.3	)	15	$	129.4	$	(2.4	)	39
Residential mortgage-backed securities	7.1		(0.2		)	25	44.1		(0.8		)	36
Commercial mortgage-backed securities	—		—			—	31.3		(0.6		)	8
Asset-backed securities	11.1		(0.1		)	4	18.3		(0.1		)	6
Total fixed maturity securities	52.8		(3.6		)	44	223.1		(3.9		)	89
Total greater than 12 months	$	52.8	$	(3.6	)	44	$	223.1	$	(3.9	)	89

Total available-for-sale:
Fixed maturity securities
U.S. Treasuries	$	27.4	$	(0.1	)	20	$	—	$	—		—
States and municipalities	—		—			—	20.6		(0.2		)	5
Corporate securities	363.0		(8.0		)	137	239.3		(3.2		)	81
Residential mortgage-backed securities	57.6		(1.0		)	49	44.1		(0.8		)	36
Commercial mortgage-backed securities	51.5		(1.0		)	22	31.3		(0.6		)	8
Asset-backed securities	45.2		(0.1		)	31	18.3		(0.1		)	6
Total fixed maturity securities	544.7		(10.2		)	259	353.6		(4.9		)	136
Equity securities	35.8		(4.6		)	45	10.1		(0.6		)	15
Total available-for-sale	$	580.5	$	(14.8	)	304	$	363.7	$	(5.5	)	151

Net realized gains and change in unrealized gains (losses), available for sale securities table

realized gains on investments and the change in unrealized gains (losses) on fixed maturity and equity securities are determined on a specific-identification basis and were as follows:



	Years Ended December 31,
	2015			2014			2013
	(in millions)
Net realized gains on investments
Fixed maturity securities
Gross gains	$	0.5		$	1.1		$	0.7
Gross losses	(0.4		)	—			—
Net realized gains on fixed maturity securities	$	0.1		$	1.1		$	0.7
Equity securities
Gross gains	$	8.1		$	15.7		$	9.1
Gross losses	(18.9		)	(0.5		)	(0.3		)
Net realized gains on equity securities	$	(10.8	)	$	15.2		$	8.8
Total	$	(10.7	)	$	16.3		$	9.5

Change in unrealized gain (losses)
Fixed maturity securities	$	(22.2	)	$	23.1		$	(88.8	)
Equity securities	(13.7		)	2.2			28.6
Total	$	(35.9	)	$	25.3		$	(60.2	)

Investment income table

Net investment income was as follows:



	Years Ended December 31,
	2015			2014			2013
	(in millions)
Fixed maturity securities	$	68.8		$	70.7		$	69.5
Equity securities	5.9			4.2			3.8
Cash equivalents and restricted cash	0.1			0.1			0.1
Gross investment income	74.8			75.0			73.4
Investment expenses	(2.6		)	(2.6		)	(2.6		)
Net investment income	$	72.2		$	72.4		$	70.8

- Definition

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

+ References + Details

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2015

Property and Equipment [Abstract]

Property, plant and equipment table

Property and equipment consists of the following:



	As of December 31,
	2015			2014
	(in millions)
Furniture and equipment	$	2.3		$	2.3
Leasehold improvements	4.3			4.4
Computers and software	56.7			46.0
Automobiles	1.2			1.2
	64.5			53.9
Accumulated amortization and depreciation	(39.6		)	(32.9		)
Property and equipment, net	$	24.9		$	21.0

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Income Taxes [Abstract]

Summary of income tax contingencies table

The provision for income taxes consisted of the following:



	Years Ended December 31,
	2015			2014			2013
Current tax expense:	(in millions)
Federal	$	9.5		$	6.3		$	0.1
State	1.1			0.1			—
Total current tax expense	10.6			6.4			0.1
Deferred federal tax benefit	(5.6		)	(0.5		)	(10.8		)
Income tax expense (benefit)	$	5.0		$	5.9		$	(10.7	)

Reconciliation of federal staturoty income tax rates to the effective tax rates table



	Years Ended December 31,
	2015			2014			2013
	(in millions)
Expense computed at statutory rate	$	34.8		$	37.3		$	18.6
Dividends received deduction and tax-exempt interest	(8.6		)	(8.8		)	(9.1		)
Pre-Privatization reserve adjustments, excluding LPT	(15.3		)	(3.6		)	(7.4		)
LPT deferred gain amortization	(4.9		)	(8.4		)	(6.6		)
LPT Reserve Adjustment	(2.2		)	(10.9		)	(6.7		)
Other	1.2			0.3			0.5
Income tax expense (benefit)	$	5.0		$	5.9		$	(10.7	)

Deferred tax assets and liabilities

The significant components of deferred income taxes, net, were as follows as of December 31:



	2015				2014
	Deferred Tax				Deferred Tax
	Assets		Liabilities		Assets		Liabilities
	(in millions)
Unrealized capital gains, net	$	—	$	45.0	$	—	$	57.6
Deferred policy acquisition costs	—		15.7		—		15.7
Intangible assets	—		3.0		—		3.2
Loss reserve discounting for tax reporting	56.3		—		56.7		—
Unearned premiums	20.9		—		20.9		—
Allowance for bad debt	4.3		—		2.7		—
Stock based compensation	4.1		—		5.8		—
Accrued liabilities	8.4		—		7.5		—
Minimum tax credit	28.0		—		19.6		—
Net operating loss carryforward	8.7		—		16.2		—
Other	8.4		7.5		2.5		5.7
Total	$	139.1	$	71.2	$	131.9	$	82.2
Deferred income taxes, net	$	67.9			$	49.7

Liability for Unpaid Losses and Loss Adjustment Expenses (Tables)

12 Months Ended

Dec. 31, 2015

Liability for Unpaid Losses and Loss Adjustment Expenses [Abstract]

Changes in the liability for unpaid losses and LAE table

The following table represents a reconciliation of changes in the liability for unpaid losses and LAE.



	Years Ended December 31,
	2015			2014		2013
	(in millions)
Unpaid losses and LAE, gross of reinsurance, at beginning of period	$	2,369.7		$	2,330.5	$	2,231.5
Less reinsurance recoverable, excluding bad debt allowance, on unpaid losses and LAE	669.5			743.1		805.4
Net unpaid losses and LAE at beginning of period	1,700.2			1,587.4		1,426.1
Losses and LAE, net of reinsurance, incurred in:
Current year	456.9			503.8		494.5
Prior years	(7.2		)	4.6		7.0
Total net losses and LAE incurred during the period	449.7			508.4		501.5
Paid losses and LAE, net of reinsurance, related to:
Current year	75.4			75.9		78.5
Prior years	355.2			319.7		261.7
Total net paid losses and LAE during the period	430.6			395.6		340.2
Ending unpaid losses and LAE, net of reinsurance	1,719.3			1,700.2		1,587.4
Reinsurance recoverable, excluding bad debt allowance, on unpaid losses and LAE	628.2			669.5		743.1
Unpaid losses and LAE, gross of reinsurance, at end of period	$	2,347.5		$	2,369.7	$	2,330.5

Reinsurance (Tables)

12 Months Ended

Dec. 31, 2015

Reinsurance [Abstract]

Supplemental schedule of reinsurance premiums for insurance companies table

Reinsurance transactions reflected in the accompanying consolidated statements of comprehensive income were as follows:



	Years Ended December 31,
	2015						2014						2013
	Written			Earned			Written			Earned			Written			Earned
	(in millions)
Direct premiums	$	684.9		$	686.0		$	686.8		$	684.3		$	680.5		$	645.4
Assumed premiums	12.8			12.8			10.9			10.3			9.4			8.3
Gross premiums	697.7			698.8			697.7			694.6			689.9			653.7
Ceded premiums	(8.4		)	(8.4		)	(10.1		)	(10.1		)	(11.4		)	(11.4		)
Net premiums	$	689.3		$	690.4		$	687.6		$	684.5		$	678.5		$	642.3
Ceded losses and LAE incurred	$	10.1					$	17.2					$	10.7

Notes Payable (Tables)

12 Months Ended

Dec. 31, 2015

Notes Payable [Abstract]

Schedule of long-term debt instruments table

Notes payable is comprised of the following:



	December 31,
	2015		2014
	(in millions)
Credit facility, with variable interest, as described below	$	—	$	60.0
Dekania Surplus Note, due April 30, 2034 with variable interest of 425 basis points above 90-day LIBOR	10.0		10.0
ICONS Surplus Note, due May 26, 2034 with variable interest of 425 basis points above 90-day LIBOR	12.0		12.0
Alesco Surplus Note, due December 15, 2034 with variable interest of 405 basis points above 90-day LIBOR	10.0		10.0
Balance	$	32.0	$	92.0

Schedule of maturities of long-term debt table

Principal payment obligations on notes payable outstanding at December 31, 2015, were as follows:



Year	Principal Due
	(in millions)
2016	$	—
2017	—
2018	—
2019	—
2020	—
Thereafter	32.0
Total	$	32.0

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21538-112644

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644

+ Details

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2015

Commitments and Contingencies [Abstract]

Operating and capital leases schedule of future minimum lease payments table

The future lease payments for the next five years on these non-cancelable operating and capital leases at December 31, 2015, were as follows:



Year	Operating Leases		Capital Leases
	(in millions)
2016	$	4.9	$	0.3
2017	4.8		0.3
2018	3.5		0.2
2019	3.0		—
2020	2.6		—
Thereafter	1.1		—
Total	$	19.9	$	0.8

Schedule of capital leased asssets table

Property held under capital leases is included in property and equipment as follows:



Asset Class	2015			2014
	(in millions)
Computers and software	$	0.4		$	0.9
Automobiles	1.2			1.2
	1.6			2.1
Accumulated amortization	(1.0		)	(1.0		)
Total	$	0.6		$	1.1

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2015

Stock-Based Compensation [Abstract]

Schedule of compensation cost for share-based payment arrangements, allocation of share-based compensation costs by plan table

Net stock-based compensation expense recognized in the accompanying consolidated statements of comprehensive income was as follows:



	Years Ended December 31,
	2015		2014		2013
Stock-based compensation expense related to:	(in millions)
Nonqualified stock options	$	1.0	$	1.2	$	1.7
RSUs	2.0		1.9		2.3
PSUs	1.6		2.9		1.6
Total	4.6		6.0		5.6
Less: related tax benefit	1.6		2.1		2.0
Net stock-based compensation expense	$	3.0	$	3.9	$	3.6

Schedule of share-based payment award, stock options, valuation assumptions table

The fair value of the stock options granted during the years ended December 31, 2015, 2014, and 2013 was calculated using the following weighted average assumptions:



	2015		2014		2013
Expected volatility	38.0	%	39.0	%	40.1	%
Expected life (in years)	4.8		4.8		4.8
Dividend yield	1.0	%	1.2	%	1.1	%
Risk-free interest rate	1.6	%	1.6	%	0.8	%
Weighted average grant date fair values of options granted	$7.63		$6.66		$7.04

Schedule of share-based compensation arrangement by share-based payment award, options, vested and expected to vest, outstanding table

Changes in outstanding stock options for the year ended December 31, 2015 were as follows:



	Number of Options		Weighted-Average Exercise Price		Weighted Average Remaining Contractual Life
Options outstanding at December 31, 2012	1,830,772		$	16.97	3.7 years
Granted	162,800		22.24		6.2 years
Exercised	(411,295	)	17.89
Expired	(6,900	)	17.00
Forfeited	(28,479	)	18.90
Options outstanding at December 31, 2013	1,546,898		17.24		3.4 years
Granted	141,744		20.87		6.2 years
Exercised	(120,494	)	17.89
Expired	(2,400	)	17.00
Forfeited	(44,458	)	19.99
Options outstanding at December 31, 2014	1,521,290		17.45		2.9 years
Granted	80,800		24.20		6.2 years
Exercised	(463,466	)	16.43
Forfeited	(17,079	)	20.21
Options outstanding at December 31, 2015	1,121,545		18.31		2.8 years
Exercisable at December 31, 2015	849,312		17.28		2.1 years

Schedule of fair value of options vested and instrinsic value of outstanding and exercisable options table

The fair value of options vested and the intrinsic value of outstanding and exercisable options as of December 31, were as follows:



	2015		2014		2013
	(in millions)
Fair value of options vested	$	1.3	$	1.6	$	1.8
Intrinsic value of outstanding options	10.1		9.2		22.3
Intrinsic value of exercisable options	8.5		7.8		15.2

Schedule of share-based compensation, restricted stock and restricted stock units activity

Changes in outstanding RSUs for the year ended December 31, 2015 were as follows:



	Number of RSUs		Weighted Average Grant Date Fair Value
RSUs outstanding at December 31, 2012	406,262		$	16.65
Granted	84,215		23.57
Forfeited	(10,924	)	18.85
Vested	(121,207	)	15.97
RSUs outstanding at December 31, 2013	358,346		18.44
Granted	87,396		21.02
Forfeited	(16,690	)	20.18
Vested	(122,185	)	18.26
RSUs outstanding at December 31, 2014	306,867		19.15
Granted	112,048		24.19
Forfeited	(7,749	)	20.99
Vested	(92,133	)	19.74
RSUs outstanding at December 31, 2015	319,033		20.71
Vested but unsettled RSUs at December 31, 2015	124,149		17.73

Schedule of fair value of RSUs vested and instrinsic value of outstanding and vested RSUs table

The grant date fair value of RSUs vested and the intrinsic value of vested RSUs for the years ended December 31, were as follows:



	2015		2014		2013
	(in millions)
Grant date fair value of RSUs vested	$	1.7	$	2.2	$	1.9
Intrinsic value of vested RSUs	2.2		2.7		2.9

PSUs awarded to certain officers table

The Company awarded PSUs to certain officers of the Company as follows:



Date of Grant	Target Number Awarded	Fair Value on Date of Grant		Aggregate Fair Value on Date of Grant
				(in millions)
March 2013⁽¹⁾	147,440	$	22.24	$	3.3
March 2014⁽¹⁾	125,340	20.87		2.6
March 2015⁽²⁾	110,000	24.20		2.7


(1)	The PSUs granted in 2013 and 2014 have a performance period of three years and are subject to certain performance goals, based on the Company's statutory combined ratio, with payouts that range from 0% to 200% of the target awards.

Statutory Matters (Tables)

12 Months Ended

Dec. 31, 2015

Stautory Matters [Abstract]

Statutory accounting practices disclosure table



	December 31,
	2015		2014
	(in millions)
Capital stock and unassigned surplus	$	498.8	$	413.8
Paid in capital	174.9		174.9
Surplus notes	32.0		32.0
Total statutory surplus	$	705.7	$	620.7

- Definition

Tabular disclosure of how the entity's reporting under GAAP as of the balance sheet date differs from the results based on prescribed and permitted accounting practices of the state or country of domicile in which a relevant statutory filing is made, or differences in results based on the National Association of Insurance Commissioners (NAIC) prescribed practices, or a combination thereof. Describes the accounting practices used and the related monetary effect on statutory surplus, net income, and risk-based capital. If an insurance enterprise's risk-based capital would have triggered a regulatory event had it not used a permitted practice, that fact is disclosed in the financial statements. Permitted statutory accounting practices include practices not prescribed but allowed by the domiciliary state insurance department regulatory authority.

+ References + Details

Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Net income and weighted average common shares outstanding used in earnings per share calculations table

The following table presents the net income and the weighted average shares outstanding used in the earnings per share common share calculations.



	Years Ended December 31,
	2015		2014		2013
	(in millions, except share data)
Net income available to stockholders–basic and diluted	$	94.4	$	100.7	$	63.8
Weighted average number of shares outstanding–basic	32,070,911		31,529,621		31,142,534
Effect of dilutive securities:
Stock options	286,764		223,811		464,334
PSUs	155,768		264,511		177,040
RSUs	48,010		51,126		154,259
Dilutive potential shares	490,542		539,448		795,633
Weighted average number of shares outstanding–diluted	32,561,453		32,069,069		31,938,167

Antidilutive securities excluded from computation of earnings per share table

The following table presents options, PSUs and RSUs that were excluded from diluted earnings per share.



	Years Ended December 31,
	2015	2014	2013
Options excluded as the exercise price was greater than the average market price	20,200	173,247	—
Options, PSUs and RSUs excluded under the treasury method, as the potential proceeds on settlement or exercise was greater than the value of shares acquired	257,405	260,171	162,800

Selected Quarterly Financial Data (Tables)

12 Months Ended

Dec. 31, 2015

Selecled Quarterly Financial Data (Unaudited) [Abstract]

Schedule of Quarterly Financial Information [Table Text Block]

Quarterly results for the years ended December 31, 2015 and 2014 were as follows:



	2015 Quarters Ended
	March 31		June 30		September 30		December 31
	(in millions, except per share data)
Net premiums earned	$	159.0	$	170.6	$	179.0	$	181.8
Net realized gains (losses) on investments	1.2		1.9		2.0		(15.8		)
Losses and loss adjustment expenses	106.2		101.5		115.8		105.9
Commission expense	18.7		22.9		21.0		22.8
Underwriting and other operating expenses	33.5		32.5		31.6		37.6
Income tax expense (benefit)	4.1		4.1		5.9		(9.1		)
Net income	14.0		29.2		24.5		26.7
Earnings per common share:
Basic	0.44		0.91		0.76		0.83
Diluted	0.43		0.90		0.75		0.82



	2014 Quarters Ended
	March 31		June 30		September 30		December 31
	(in millions, except per share data)
Net premiums earned	$	167.2	$	172.6	$	172.1	$	172.6
Net realized gains on investments	3.3		9.2		1.8		2.0
Losses and loss adjustment expenses	122.3		98.5		122.4		110.2
Commission expense	20.0		20.4		20.6		20.4
Underwriting and other operating expenses	33.3		33.1		31.9		30.9
Income tax expense	1.3		2.0		1.3		1.3
Net income	10.8		45.6		15.2		29.1
Earnings per common share:
Basic	0.34		1.45		0.48		0.92
Diluted	0.34		1.42		0.47		0.91

Schedule II. Condensed Financial Information of Registrant (Tables)

12 Months Ended

Dec. 31, 2015

Notes to Condensed Financial Statments [Abstract]

Investments classified by contractual maturity date table



	Amortized Cost		Estimated Fair Value
	(in millions)
Due in one year or less	$	113.6	$	115.1
Due after one year through five years	859.3		884.5
Due after five years through ten years	636.9		657.1
Due after ten years	252.4		267.7
Mortgage and asset-backed securities	358.9		364.1
Total	$	2,221.1	$	2,288.5



	Amortized Cost		Estimated Fair Value
	(in millions)
Due in one year or less	$	14.6	$	14.9
Due after one year through five years	15.6		16.1
Due after five years through ten years	3.3		3.7
Due after ten years	6.7		7.5
Total	$	40.2	$	42.2

Schedule II - Balance Sheet Parenthetical (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fixed maturity securities, amortized cost	$ 2,358,600	$ 2,283,900
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	55,589,454	54,866,802
Common stock, shares outstanding (in shares)	32,216,480	31,493,828
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000
Preferred stock, shares issued (in shares)	0	0
Treasury stock, at cost (in shares)	23,372,974	23,372,974
Parent Company [Member]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000
Preferred stock, shares issued (in shares)	0	0
Equity Securities [Member]
Fixed maturity securities, amortized cost	$ 137,500	$ 97,800
Equity Securities [Member] \| Parent Company [Member]
Fixed maturity securities, amortized cost	46,800	48,600
Debt Securities [Member]
Fixed maturity securities, amortized cost	2,221,100	2,186,100
Debt Securities [Member] \| Parent Company [Member]
Fixed maturity securities, amortized cost	$ 40,200	$ 83,300

Changes in Estimates (Details) - USD ($)
$ / shares in Units, $ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2015

Sep. 30, 2015

Jun. 30, 2015

Mar. 31, 2015

Dec. 31, 2014

Sep. 30, 2014

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Change in Accounting Estimate [Line Items]

Unpaid losses and loss adjustment expenses

$ 2,347,500

$ 2,369,700

$ 2,347,500

$ 2,369,700

$ 2,330,500

$ 2,231,500

Amortization of deferred gain

(11,400)

(13,100)

(14,600)

Reserves reallocated to taxable years

36,900

56,300

13,100

27,200

Net income

$ 26,700

$ 24,500

$ 29,200

$ 14,000

$ 29,100

$ 15,200

$ 45,600

$ 10,800

$ 94,400

$ 100,700

$ 63,800

Basic

$ 0.83

$ 0.76

$ 0.91

$ 0.44

$ 0.92

$ 0.48

$ 1.45

$ 0.34

$ 2.94

$ 3.19

$ 2.05

Diluted

$ 0.82

$ 0.75

$ 0.90

$ 0.43

$ 0.91

$ 0.47

$ 1.42

$ 0.34

$ 2.90

$ 3.14

$ 2.00

Change to Contingent Profit Commission [Member]

Change in Accounting Estimate [Line Items]

Amortization of deferred gain

$ (2,900)

$ (2,600)

$ (10,800)

^[1]

$ (4,300)

^[1]

Net income

$ 2,900

$ 2,600

$ 10,800

$ 4,300

Basic

$ 0.08

$ 0.34

$ 0.14

Diluted

$ 0.08

$ 0.34

$ 0.13

EPS, basic and diluted

$ 0.09

Change Due to Estimated Reserves Ceded Under the LPT Agreement [Member]

Change in Accounting Estimate [Line Items]

Unpaid losses and loss adjustment expenses

$ (10,000)

$ (46,800)

$ (10,000)

$ (46,800)

$ (27,500)

Amortization of deferred gain

(8,800)

(6,400)

^[2]

(31,100)

^[2]

(19,000)

^[2]

Net income

$ 8,800

$ 6,400

$ 31,100

$ 19,000

Basic

$ 0.28

$ 0.20

$ 0.99

$ 0.61

Diluted

$ 0.27

$ 0.20

$ 0.97

$ 0.59

Due to change in reserves for non-taxable periods

Change in Accounting Estimate [Line Items]

Effective Income Tax Rate Reconciliation, Percent

(65.30%)

(15.40%)

(3.40%)

(13.90%)

Net income

$ 11,500

$ 15,300

$ 3,600

$ 7,400

Basic

$ 0.36

$ 0.48

$ 0.11

$ 0.24

Diluted

$ 0.35

$ 0.47

$ 0.11

$ 0.23

[1]	(1)The cumulative adjustments to the Deferred Gain were also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, so that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.
[2]	(1)The cumulative adjustments to the Deferred Gain were also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, so that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.

Summary of Significant Accounting Policies Reinsurance Funds Held (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Reinsurance [Line Items]
Restricted cash and cash equivalents	$ 2,500	$ 10,800
Funds Held in Trust, Reinsurance Agreement [Domain]
Reinsurance [Line Items]
Restricted cash and cash equivalents	$ 2,500	$ 6,100

Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Investments	$ 2,487,200	$ 2,448,400
Premiums receivable from policyholders for final audit	53,500	49,100
Premiums receivable, bad debt allowance	12,200	7,900
Write-offs, net of recoveries of amounts previously written off	2,400	3,400	$ 2,500
Deferred policy acquisition cost, amortization expense	$ 103,900	102,700	96,900
Reinsurance quota share, percentage	100.00%
Unpaid losses	$ 628,200	669,500
LPT actual amounts paid versus expected amounts, period	every five years
LPT actual amounts paid versus expected amounts, expiration period	first twenty-five years
LPT favorable/ unfavorable difference, percentage	30.00%
LPT - loss expense as a percentange of losses paid, for management of LPT claims	7.00%
Collateralized by cash or letter of credit	$ 3,700
LPT collateral held in trust account	1,400,000
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Intangible assets, gross carrying amount	17,100	17,100
Intangible assets, accumulated amortization	(8,600)	(8,100)
Intangible assets, net	8,500	9,000
Amortization of intangible assets	500	700	$ 900
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Future amortization expense, year two	400
Future amortization expense, year three	300
Future amortization expense, year four	100
Intangible assets, future amortization total	800
Licensing Agreements [Member]
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Intangible assets, gross carrying amount	7,700	7,700
Intangible assets, net	7,700	7,700
Service Agreements [Member]
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Intangible assets, gross carrying amount	9,400	9,400
Intangible assets, accumulated amortization	(8,600)	(8,100)
Intangible assets, net	$ 800	1,300
Leasehold Improvements [Member]
Finite-Lived Intangible Assets, Amortization Method	amortized over three to five years
Electronic Data Processing Equipment, Software, Furniture and Equipment and Automobiles [Member]
Finite-Lived Intangible Assets, Amortization Method	straight-line method over three to seven years
Portion at Fair Value Measurement [Member]
Investments	$ 32,700	$ 33,300

Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments	$ 2,487,200	$ 2,448,400
Cash and cash equivalents	56,600	103,600	$ 34,500	$ 140,700
Restricted cash and cash equivalents	2,500	10,800
Notes payable	32,000	92,000
Investments, fair value	2,487,200	2,448,400
Cash and cash equivalents, estimated fair value	56,600	103,600
Notes payable, fair value	$ 36,600	$ 97,800

Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 2,358,600	$ 2,283,900
Gross unrealized gains	143,400	170,000
Gross unrealized loss	(14,800)	(5,500)
Investments	2,487,200	2,448,400
Deposit Assets
Investments	2,487,200	2,448,400
Assets Held-in-trust
Investments	2,487,200	2,448,400
Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	2,221,100	2,186,100
Gross unrealized gains	77,600	94,500
Gross unrealized loss	(10,200)	(4,900)
Investments	2,288,500	2,275,700
Deposit Assets
Investments	2,288,500	2,275,700
Assets Held-in-trust
Investments	2,288,500	2,275,700
US Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	116,400	160,900
Gross unrealized gains	3,900	5,800
Gross unrealized loss	(100)	0
Investments	120,200	166,700
Deposit Assets
Investments	120,200	166,700
Assets Held-in-trust
Investments	120,200	166,700
US Government Agencies Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	23,000	37,200
Gross unrealized gains	1,400	2,400
Gross unrealized loss	0	0
Investments	24,400	39,600
Deposit Assets
Investments	24,400	39,600
Assets Held-in-trust
Investments	24,400	39,600
US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	809,400	701,600
Gross unrealized gains	45,100	44,400
Gross unrealized loss	0	(200)
Investments	854,500	745,800
Deposit Assets
Investments	854,500	745,800
Assets Held-in-trust
Investments	854,500	745,800
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	913,400	880,700
Gross unrealized gains	19,900	30,800
Gross unrealized loss	(8,000)	(3,200)
Investments	925,300	908,300
Deposit Assets
Investments	925,300	908,300
Assets Held-in-trust
Investments	925,300	908,300
Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	46,000	61,600
Gross unrealized gains	0	0
Gross unrealized loss	(100)	(100)
Investments	45,900	61,500
Deposit Assets
Investments	45,900	61,500
Assets Held-in-trust
Investments	45,900	61,500
Residential Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	231,800	278,600
Gross unrealized gains	7,100	10,600
Gross unrealized loss	(1,000)	(800)
Investments	237,900	288,400
Deposit Assets
Investments	237,900	288,400
Assets Held-in-trust
Investments	237,900	288,400
Commercial Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	81,100	65,500
Gross unrealized gains	200	500
Gross unrealized loss	(1,000)	(600)
Investments	80,300	65,400
Deposit Assets
Investments	80,300	65,400
Assets Held-in-trust
Investments	80,300	65,400
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	137,500	97,800
Gross unrealized gains	65,800	75,500
Gross unrealized loss	(4,600)	(600)
Investments	198,700	172,700
Deposit Assets
Investments	198,700	172,700
Assets Held-in-trust
Investments	198,700	172,700
Funds Held in Trust, Reinsurance Agreement [Domain]
Schedule of Available-for-sale Securities [Line Items]
Investments		74,600
Deposit Assets
Investments		74,600
Assets Held-in-trust
Investments		74,600
Portion at Fair Value Measurement [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments	32,700	33,300
Deposit Assets
Investments	32,700	33,300
Assets Held-in-trust
Investments	32,700	33,300
Portion at Fair Value Measurement [Member] \| Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments	881,200	783,900
Deposit Assets
Investments	881,200	783,900
Assets Held-in-trust
Investments	$ 881,200	$ 783,900

Investments, Amortized Cost and Estimated Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Amortized Cost
Due in one year or less, amortized cost	$ 113,600
Due after one year through five years, amortized cost	859,300
Due after five years through ten years, amortized cost	636,900
Due after ten years, amortized cost	252,400
Mortgage and asset-backed securities, amortized cost	358,900
Total, amortized cost	2,221,100
Estimated Fair Value
Due in one year or less, fair value	115,100
Due after one year through five years, fair value	884,500
Due after five years through ten years, fair value	657,100
Due after ten years, fair value	267,700
Mortgage and asset-backed securities, fair value	364,100
Total, fair value	$ 2,288,500	$ 2,275,700

Investments, Continuous Loss Position (Details) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($) shares	Dec. 31, 2013 USD ($) shares
Estimated Fair Value
Estimated fair value, less than 12 months	$ 527.7	$ 140.6
Estimated fair value, 12 months or greater	52.8	223.1
Estimated fair value, total	580.5	363.7
Gross Unrealized Losses
Gross unrealized losses, less than 12 Months	11.2	1.6
Gross unrealized losses, 12 months or greater	3.6	3.9
Estimated unrealized loss, total position	$ 14.8	$ 5.5
Number of issues in loss position, less than 12 months \| shares	260	62
Number of issues in loss position, 12 months or greater \| shares	44	89
Number of issues in loss position, aggregate \| shares	304	151
Total impairments, value	$ 17.2	$ 0.5	$ 0.1
Total impairments, number of securitites \| shares	27	7	1
Debt Securities [Member]
Estimated Fair Value
Estimated fair value, less than 12 months	$ 491.9	$ 130.5
Estimated fair value, 12 months or greater	52.8	223.1
Estimated fair value, total	544.7	353.6
Gross Unrealized Losses
Gross unrealized losses, less than 12 Months	6.6	1.0
Gross unrealized losses, 12 months or greater	3.6	3.9
Estimated unrealized loss, total position	$ 10.2	$ 4.9
Number of issues in loss position, less than 12 months \| shares	215	47
Number of issues in loss position, 12 months or greater \| shares	44	89
Number of issues in loss position, aggregate \| shares	259	136
US Treasury Securities [Member]
Estimated Fair Value
Estimated fair value, less than 12 months	$ 27.4	$ 0.0
Estimated fair value, total	27.4	0.0
Gross Unrealized Losses
Gross unrealized losses, less than 12 Months	0.1	0.0
Estimated unrealized loss, total position	$ 0.1	$ 0.0
Number of issues in loss position, less than 12 months \| shares	20	0
Number of issues in loss position, aggregate \| shares	20	0
US States and Political Subdivisions Debt Securities [Member]
Estimated Fair Value
Estimated fair value, less than 12 months	$ 0.0	$ 20.6
Estimated fair value, total	0.0	20.6
Gross Unrealized Losses
Gross unrealized losses, less than 12 Months	0.0	0.2
Estimated unrealized loss, total position	$ 0.0	$ 0.2
Number of issues in loss position, less than 12 months \| shares	0	5
Number of issues in loss position, aggregate \| shares	0	5
Corporate Debt Securities [Member]
Estimated Fair Value
Estimated fair value, less than 12 months	$ 328.4	$ 109.9
Estimated fair value, 12 months or greater	34.6	129.4
Estimated fair value, total	363.0	239.3
Gross Unrealized Losses
Gross unrealized losses, less than 12 Months	4.7	0.8
Gross unrealized losses, 12 months or greater	3.3	2.4
Estimated unrealized loss, total position	$ 8.0	$ 3.2
Number of issues in loss position, less than 12 months \| shares	122	42
Number of issues in loss position, 12 months or greater \| shares	15	39
Number of issues in loss position, aggregate \| shares	137	81
Residential Mortgage Backed Securities [Member]
Estimated Fair Value
Estimated fair value, less than 12 months	$ 50.5	$ 0.0
Estimated fair value, 12 months or greater	7.1	44.1
Estimated fair value, total	57.6	44.1
Gross Unrealized Losses
Gross unrealized losses, less than 12 Months	0.8	0.0
Gross unrealized losses, 12 months or greater	0.2	0.8
Estimated unrealized loss, total position	$ 1.0	$ 0.8
Number of issues in loss position, less than 12 months \| shares	24	0
Number of issues in loss position, 12 months or greater \| shares	25	36
Number of issues in loss position, aggregate \| shares	49	36
Commercial Mortgage Backed Securities [Member]
Estimated Fair Value
Estimated fair value, less than 12 months	$ 51.5	$ 0.0
Estimated fair value, 12 months or greater	0.0	31.3
Estimated fair value, total	51.5	31.3
Gross Unrealized Losses
Gross unrealized losses, less than 12 Months	1.0	0.0
Gross unrealized losses, 12 months or greater	0.0	0.6
Estimated unrealized loss, total position	$ 1.0	$ 0.6
Number of issues in loss position, less than 12 months \| shares	22	0
Number of issues in loss position, 12 months or greater \| shares	0	8
Number of issues in loss position, aggregate \| shares	22	8
Asset-backed Securities [Member]
Estimated Fair Value
Estimated fair value, less than 12 months	$ 34.1	$ 0.0
Estimated fair value, 12 months or greater	11.1	18.3
Estimated fair value, total	45.2	18.3
Gross Unrealized Losses
Gross unrealized losses, less than 12 Months	0.0	0.0
Gross unrealized losses, 12 months or greater	0.1	0.1
Estimated unrealized loss, total position	$ 0.1	$ 0.1
Number of issues in loss position, less than 12 months \| shares	27	0
Number of issues in loss position, 12 months or greater \| shares	4	6
Number of issues in loss position, aggregate \| shares	31	6
Equity Securities [Member]
Estimated Fair Value
Estimated fair value, less than 12 months	$ 35.8	$ 10.1
Estimated fair value, total	35.8	10.1
Gross Unrealized Losses
Gross unrealized losses, less than 12 Months	4.6	0.6
Estimated unrealized loss, total position	$ 4.6	$ 0.6
Number of issues in loss position, less than 12 months \| shares	45	15
Number of issues in loss position, aggregate \| shares	45	15

Investments, Net Realized Gains (Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net realized gains (losses)
Net realized (losses) gains on investments	$ (10,700)	$ 16,300	$ 9,500
Change in unrealized gains (losses)
Change in unrealized gains (losses) on fixed maturity and equity securities	(35,900)	25,300	(60,200)
Debt Securities [Member]
Net realized gains (losses)
Gross gains from sales	500	1,100	700
Gross losses from sales	(400)	0	0
Net realized (losses) gains on investments	100	1,100	700
Change in unrealized gains (losses)
Change in unrealized gains (losses) on fixed maturity and equity securities	(22,200)	23,100	(88,800)
Equity Securities [Member]
Net realized gains (losses)
Gross gains from sales	8,100	15,700	9,100
Gross losses from sales	(18,900)	(500)	(300)
Net realized (losses) gains on investments	(10,800)	15,200	8,800
Change in unrealized gains (losses)
Change in unrealized gains (losses) on fixed maturity and equity securities	$ (13,700)	$ 2,200	$ 28,600

Net Investment Income (Details) - USD ($) $ in Millions	12 Months Ended
Net Investment Income (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Available-for-sale Securities	$ 2,487.2	$ 2,448.4
Investment income	74.8	75.0	$ 73.4
Investment expenses	(2.6)	(2.6)	(2.6)
Net investment income	72.2	72.4	70.8
Debt Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income related to fixed maturity securities and short-term investments and cash equivalents	68.8	70.7	69.5
Equity Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income related to equity securities	5.9	4.2	3.8
Short-term Investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income related to fixed maturity securities and short-term investments and cash equivalents	0.1	0.1	$ 0.1
Portion at Fair Value Measurement [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Available-for-sale Securities	$ 32.7	$ 33.3

Property and Equipment Property and Equipment breakout (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property and Equipment [Line Items]
Property and equipment, gross	$ 64,500	$ 53,900
Accumulated depreciation, depletion and amortization, property and equipment	39,600	32,900
Property and equipment, net	24,900	21,000
Utilities operating expense, depreciation and amortization	7,800	6,300	$ 5,200
Payments to develop software	1,200	800
Office Equipment [Member]
Property and Equipment [Line Items]
Property and equipment, gross	2,300	2,300
Leasehold Improvements [Member]
Property and Equipment [Line Items]
Property and equipment, gross	4,300	4,400
Computer Equipment [Member]
Property and Equipment [Line Items]
Property and equipment, gross	56,700	46,000
Automobiles [Member]
Property and Equipment [Line Items]
Property and equipment, gross	$ 1,200	$ 1,200

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current federal tax expense (benefit)									$ 9,500	$ 6,300	$ 100
Current state and local tax expense (benefit)									1,100	100	0
Current income tax expense (benefit)									10,600	6,400	100
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Deferred income tax benefit									(5,600)	(500)	(10,800)
Income tax expense (benefit)	$ (9,100)	$ 5,900	$ 4,100	$ 4,100	$ 1,300	$ 1,300	$ 2,000	$ 1,300	$ 5,000	5,900	(10,700)
Statutory federal tax rate									35.00%
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Expense computed at statutory rate									$ 34,800	37,300	18,600
Dividends received deduction and tax-exempt interest									(8,600)	(8,800)	(9,100)
Pre-privatization reserve adjustment									(15,300)	(3,600)	(7,400)
LPT deferred gain amortization									(4,900)	(8,400)	(6,600)
LPT reserve adjustment									(2,200)	(10,900)	(6,700)
Income tax reconciliation, other									1,200	300	500
Downward adjustment of pre-privatization unpaid loss reserve									56,300	13,100	27,200
Net income	26,700	$ 24,500	$ 29,200	$ 14,000	29,100	$ 15,200	$ 45,600	$ 10,800	94,400	100,700	63,800
Deferred Tax Liabilities [Abstract]
Unrealized capital gains, net	45,000				57,600				45,000	57,600
Deferred policy acquisition cost	15,700				15,700				15,700	15,700
Intangible assets	3,000				3,200				3,000	3,200
Other deferred tax liabilities	7,500				5,700				7,500	5,700
Total deferred tax liabilities	71,200				82,200				71,200	82,200
Deferred Tax Assets [Abstract]
Loss reserves discounting for tax reporting	56,300				56,700				56,300	56,700
Unearned premiums	20,900				20,900				20,900	20,900
Allowance for bad debt	4,300				2,700				4,300	2,700
Stock based compensation	4,100				5,800				4,100	5,800
Accrued liabilities	8,400				7,500				8,400	7,500
Minimum tax credit	28,000				19,600				28,000	19,600
Net operating loss carry forward	8,700				16,200				8,700	16,200
Other deferred tax assets	8,400				2,500				8,400	2,500
Total deferred tax assets	139,100				131,900				139,100	131,900
Deferred income taxes, net	67,900				49,700				67,900	49,700
Operating loss carryforwards	25,000								25,000
Minimum tax credit	$ 28,000								28,000
Change Due to Estimated Reserves Ceded Under the LPT Agreement [Member]
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Net income					8,800				6,400	31,100	19,000
Change to Contingent Profit Commission [Member]
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Net income					$ 2,900				$ 2,600	$ 10,800	$ 4,300

Liability for Unpaid Losses and Loss Adjustment Expenses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Unpaid losses and LAE, gross of reinsurance, at beginning of period		$ 2,369,700	$ 2,330,500	$ 2,231,500
Loss reinsurance recoverable, excluding bad debt, on unpaid losses		669,500	743,100	805,400
Net unpaid losses and LAE at beginning of period		1,700,200	1,587,400	1,426,100
Losses and LAE, net of reinsurance, incurred in:
Current year		456,900	503,800	494,500
Prior years	$ 8,500	(7,200)	4,600	7,000
Total net losses and LAE incurred during the period		449,700	508,400	501,500
Deduct payments for losses and LAE, net of reinsurance, related to:
Current year		75,400	75,900	78,500
Prior years		355,200	319,700	261,700
Total net payments for losses and LAE during the period		430,600	395,600	340,200
Ending unpaid losses and LAE, net of reinsurance	1,719,300	1,719,300	1,700,200	1,587,400
Loss reinsurance recoverable, excluding bad debt, on unpaid losses	628,200	628,200	669,500	743,100
Unpaid losses and LAE, gross of reinsurance, at end of period	2,347,500	2,347,500	2,369,700	2,330,500
Salvage and subrogation recoveries, value	26,800	$ 26,800	$ 25,100
Losses and LAE actual paid were more than expected
Losses and LAE, net of reinsurance, incurred in:
Prior years				5,000
Related to involuntary assigned risk business
Losses and LAE, net of reinsurance, incurred in:
Prior years	$ 500			$ 1,900

Reinsurance Reinsurance Premium Note (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Premiums Written, Net
Direct premiums, written		$ 684.9	$ 686.8	$ 680.5
Assumed premiums written		12.8	10.9	9.4
Gross premiums, written		697.7	697.7	689.9
Ceded premiums written		(8.4)	(10.1)	(11.4)
Premiums written, net	$ 678.5	689.3	687.6	678.5
Premiums Earned, Net
Direct premiums earned		686.0	684.3	645.4
Assumed premiums earned		12.8	10.3	8.3
Gross premiums, earned		698.8	694.6	653.7
Ceded premiums earned		(8.4)	(10.1)	(11.4)
Premiums earned, net		690.4	684.5	642.3
Ceded losses and LAE incurred		$ 10.1	$ 17.2	$ 10.7

Reinsurance Excess of Loss (Details) $ in Millions	Dec. 31, 2015 USD ($)
Excess of Loss [Abstract]
Minimum reinsurance for losses from single occurence or event	$ 7.0
Maximum reinsurance for losses from single occurence or event	$ 200.0

Reinsurance LPT Agreement (Details) - USD ($)
$ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2014

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Reinsurance Agreement [Line Items]

Unpaid losses

$ 669,500

$ 628,200

$ 669,500

Recoverables was related to the LPT agreement

534,800

$ 498,000

534,800

Reinsurance quota share, percentage

100.00%

Ceded premiums written

$ 8,400

10,100

$ 11,400

Coverage provided under LPT agreement

2,000,000

Paid losses and LAE claims related to LPT

695,200

Amortization of deferred gain

11,400

13,100

14,600

LPT Agreement [Member]

Reinsurance Agreement [Line Items]

Cash

11,700

Liabilities for the incurred but unpaid losses and LAE related to claims prior to July 1, 1995

1,500,000

Ceded premiums written

775,000

Change Due to Estimated Reserves Ceded Under the LPT Agreement [Member]

Reinsurance Agreement [Line Items]

Amortization of deferred gain

8,800

6,400

^[1]

31,100

^[1]

19,000

^[1]

Change to Contingent Profit Commission [Member]

Reinsurance Agreement [Line Items]

Amortization of deferred gain

$ 2,900

$ 2,600

$ 10,800

^[2]

$ 4,300

^[2]

[1]	(1)The cumulative adjustments to the Deferred Gain were also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, so that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.
[2]	(1)The cumulative adjustments to the Deferred Gain were also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, so that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.

Notes Payable Outstanding (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Debt Instrument [Line Items]
Notes payable	$ 32,000	$ 92,000
Line of credit facility, decrease, repayments	60,000
Cash paid for interest	2,800	3,000	$ 3,300
Line of Credit [Member]
Debt Instrument [Line Items]
Notes payable	0	60,000	70,000	$ 80,000	$ 90,000	$ 100,000
Cash paid for interest	1,300	1,400	1,600
Dekania Surplus Note [Member]
Debt Instrument [Line Items]
Notes payable	$ 10,000	10,000
Notes payable, maturity date	Apr. 30, 2034
Notes payable, callable	second quarter of 2009
Interest rate, basis points in excess of the 90-day LIBOR	425
Cash paid for interest	$ 500	500	500
Accrued interest	100	100
ICONS Surpuls Note [Member]
Debt Instrument [Line Items]
Notes payable	$ 12,000	12,000
Notes payable, maturity date	May 26, 2034
Notes payable, callable	second quarter of 2009
Interest rate, basis points in excess of the 90-day LIBOR	425
Cash paid for interest	$ 600	500	600
Accrued interest	100	100
Alesco Surplus Note [Member]
Debt Instrument [Line Items]
Notes payable	$ 10,000	10,000
Notes payable, maturity date	Dec. 15, 2034
Notes payable, callable	fourth quarter of 2009
Interest rate, basis points in excess of the 90-day LIBOR	405
Cash paid for interest	$ 400	400	$ 400
Accrued interest	$ 100	$ 100

Notes Payable Principal payment obligations on notes payable outstanding (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Capitalization, Long-term Debt [Line Items]
Repayments of principal in next twelve months	$ 0
Repayments of principal in year two	0
Repayments of principal in year three	0
Repayments of principal in year four	0
Repayments of principal in year five	0
Repayments of principal after year five	32,000
Notes payable	$ 32,000	$ 92,000

Commitments and Contingencies Future Lease Payments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Commitments and Contingencies [Abstract]
Remaining lease terms expire over the next	6 years
Future lease payments for non-cancelable operating and capital leases, in years	5 years
Operating Leases, Future Minimum Payments Due [Abstract]
Operating leases, future minimum payments due, current	$ 4.9
Operating leases, future minimum payments, due in two years	4.8
Operating leases, future minimum payments, due in three years	3.5
Operating leases, future minimum payments, due in four years	3.0
Operating leases, future minimum payments, due in five years	2.6
Operating leases, future minimum payments, due thereafter	1.1
Operating leases, future minimum payments due	19.9
Capital Leases, Future Minimum Payments Due [Abstract]
Capital leases, future minimum payments due, current	0.3
Capital leases, future minimum payments due in two years	0.3
Capital leases, future minimum payments due in three years	0.2
Capital leases, future minimum payments due in four years	0.0
Capital leases, future minimum payments due in five years	0.0
Capital leases, Future minimum payments due thereafter	0.0
Capital leases, future minimum payments due	0.8
Future interest charges included in capital lease payments	0.1
Facilities rent expense	$ 4.9	$ 4.8	$ 5.0

Commitments and Contingencies Property held under capital leases is included in property and equipment (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Property held under capital leases
Accumulated depreciation, depletion and amortization, property and equipment	$ (39.6)	$ (32.9)
Computers and software
Property held under capital leases
Property held under captial leases	0.4	0.9
Automobiles [Member]
Property held under capital leases
Property held under captial leases	1.2	1.2
Assets Held under Capital Leases [Member]
Property held under capital leases
Property held under captial leases	1.6	2.1
Accumulated depreciation, depletion and amortization, property and equipment	(1.0)	(1.0)
Total property held under capital leases	$ 0.6	$ 1.1

Commitments and Contingencies Contingencies Surrounding Insurance Assessments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Loss Contingencies [Line Items]
Amount of Insurance-related assessment liability	$ 22.0	$ 18.8
Payment period for assessment liability based on individual states regulations	one to eighty year periods
Other assets, prepaid policy surcharges	$ 21.4	$ 13.0
Expected realization period for assets related to policy surcharges	one to ten year periods

Stockholders' Equity (Details)	96 Months Ended
Stockholders' Equity (Details)	Dec. 31, 2014 $ / shares shares
Accelerated Share Repurchases [Line Items]
Stock repurchased during period, shares \| shares	23,372,974
Accelerated share repurchases, final price paid per share \| $ / shares	$ 15.51

Stock-Based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares reserved for grants	7,105,838
Stock-based compensation expense [Abstract]
Stock-based compensation expense	$ 4.6	$ 6.0	$ 5.6
Less: related tax benefit	1.6	2.1	2.0
Net stock-based compensation expense	3.0	3.9	3.6
Stock Option [Member]
Stock-based compensation expense [Abstract]
Stock-based compensation expense	1.0	1.2	1.7
Restricted stock units (RSUs)
Stock-based compensation expense [Abstract]
Stock-based compensation expense	2.0	1.9	2.3
Performance shares units [Member]
Stock-based compensation expense [Abstract]
Stock-based compensation expense	$ 1.6	$ 2.9	$ 1.6

Stock-Based Compensation Fair Market Value of Stock Options Granted, Calculated (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Fair Market Value of Stock Options Granted, Calculated [Abstract]
Expected volatility	38.00%	39.00%	40.10%
Expected life (in years)	4 years 274 days	4 years 274 days	4 years 274 days
Dividend yield	1.00%	1.20%	1.10%
Risk free interest rate	1.60%	1.60%	0.80%
Weighted average grant date fair value	$ 7.63	$ 6.66	$ 7.04

Stock-Based Compensation Changes in Outstanding Stock Options (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value	$ 7.63	$ 6.66	$ 7.04
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of outstanding options or share units	1,121,545	1,521,290	1,546,898	1,830,772
Number of options or share units, granted	80,800	141,744	162,800
Stock-options exercised, shares	(463,466)	(120,494)	(411,295)
Number of options or share units, expired		(2,400)	(6,900)
Number of options or share units, forfeited	(17,079)	(44,458)		(28,479)
Number of exercisable options or share units	849,312
Weighted average exercise price, grants	$ 24.20	$ 20.87	$ 22.24
Weighted average exercise price, exercises	16.43	17.89	17.89
Weighted average exercise price, expirations		17.00	17.00
Weighted average exercise price, forfeitures	20.21	19.99		$ 18.90
Weighted average exercise price, outstanding	18.31	$ 17.45	$ 17.24	$ 16.97
Weighted average exercisable price	$ 17.28
Weighted average remaining contractual life	2 years 300 days	2 years 324 days	3 years 164 days	3 years 269 days
Share-based compensation expense, deferred	$ 1.4
Share-based compensation expense, Period for Recognition	39 months
Options vested, fair value	$ 1.3	$ 1.6	$ 1.8
Options outstanding, intrinsic value	10.1	9.2	22.3
Options exercisable, intrinsic value	8.5	7.8	15.2
Options exercised, intrinsic value	$ 4.0	$ 0.5	$ 3.7
Stock Options Granted [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining contractual life	6 years 73 days	6 years 73 days		6 years 80 days
Stock Options Exercisable [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining contractual life	2 years 45 days
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service vesting period for options awarded	4 years
Vesting rights for options awarded	vest 25% on or after each of the subsequent four anniversaries of such date
Number of outstanding options or share units	319,033	306,867	358,346	406,262
Number of options or share units, granted	112,048	87,396	84,215
Number of options or share units, forfeited	(7,749)	(16,690)		(10,924)
Number of vested options or share units	(92,133)	(122,185)	(121,207)
Weighted average exercise price, grants	$ 24.19	$ 21.02	$ 23.57
Weighted average exercise price, forfeitures	20.99	20.18		$ 18.85
Weighted average exercise price, vested	19.74	18.26	15.97
Weighted average grant date fair value	$ 20.71	$ 19.15	$ 18.44	$ 16.65
Share-based compensation expense, deferred	$ 3.2
Share-based compensation expense, Period for Recognition	39 months
Options vested, fair value	$ 1.7	$ 2.2	$ 1.9
Options outstanding, intrinsic value	8.7	7.2	11.3
Options exercisable, intrinsic value	$ 2.2	$ 2.7	$ 2.9
Restricted Stock Units Vested but Unsettled [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of outstanding options or share units	124,149
Weighted average grant date fair value	$ 17.73

Stock-Based Compensation Performance Share Awards (Details) - USD ($)
$ / shares in Units, $ in Millions

12 Months Ended

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance share awards, minimum payout

0.00%

Performane share awards, maximum payout

200.00%

Performance share awards, expected target

200.00%

80.00%

Performance share awards, ultimate payout

0.00%

Performance shares units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Service vesting period for options awarded

3 years

Number of outstanding options or share units

110,000

^[1]

125,340

^[2]

147,440

^[2]

Share-based compensation options, exercise price on grant date

$ 24.20

^[1]

$ 20.87

^[2]

$ 22.24

^[2]

Fair value of awards awarded on grant date

$ 2.7

^[1]

$ 2.6

^[2]

$ 3.3

^[2]

Share-based compensation expense, deferred

$ 4.4

Share-based compensation expense, Period for Recognition

24 months

[1]	The PSUs awarded in March 2015 were awarded to certain officers of the Company and have a performance period of two years followed by an additional one year vesting period. The PSU awards are subject to certain performance goals with payouts that range from 0% to 200% of the target awards. The value shown in the table represents the aggregate number of PSUs awarded at the target level.
[2]	The PSUs granted in 2013 and 2014 have a performance period of three years and are subject to certain performance goals, based on the Company's statutory combined ratio, with payouts that range from 0% to 200% of the target awards. The ultimate payout of the PSUs awarded in 2013 was 0% of the target award.

Statutory Matters Statutory Matters (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statutory Accounting Practices [Line Items]
Capital stock and unassigned surplus	$ 498,800	$ 413,800
Paid in capital	174,900	174,900
Surplus notes	32,000	32,000
Total statutory surplus	705,700	620,700
SAP, net income amount	87,800	58,600	$ 19,300
Total stockholders’ equity	$ 760,800	$ 686,800
Will maintain a risk based capital (RBC) level of at least	350.00%
EICN
Statutory Accounting Practices [Line Items]
Capital stock and unassigned surplus	$ 423,100
Maximum dividends that may be paid without prior approval in 2015	$ 49,700
Extraordinary dividends, approves or does not disapprove the payment within	30 days
Percentage of surplus of EICN's statutory surplus as regards to policyholders	10.00%
EPIC
Statutory Accounting Practices [Line Items]
Maximum dividends that may be paid without prior approval in 2015	$ 28,100
Percentage of surplus used to calculate the lesser of 10% of surplus or net income, not including realized capital gains, plus a 2-year carry forward.	10.00%
Percentage of surplus used to calculate 10% of surplus, with dividends payable limited to unassigned funds minus 25% of unrealized capital gains	10.00%
Percentage of surplus used to calculate the lesser of 10% of surplus or net investment income plus a 3-year carry forward with dividends payable limited to unassigned funds minus 25% of unrealized capital gains	10.00%
Percentage of unassigned gains used to calculate 10% of surplus, with dividends payable limited to unassigned funds minus 25% of unrealized capital gains	25.00%
Percentage of unassigned gains used to calculate the lesser of 10% of surplus or net investment income plus a 3-year carry forward with dividends payable limited to unassigned funds minus 25% of unrealized capital gains	25.00%
ECIC
Statutory Accounting Practices [Line Items]
ECIC must initiate discussions of its business plan with the California DOI if its premium to policyholder surplus ratio exceeds	1.5 to 1
ECIC will not exceed a ratio of premium to policyholder surplus of	2 to 1
If at any time ECIC's policyholder surplus decreases to	80.00%
EAC and EPIC
Statutory Accounting Practices [Line Items]
Total statutory surplus	$ 4,000
Florida statute section 624.408 requires EPIC and EAC to maintain minimum capital and surplus of the greater of $4.0 million or 10% of total liabilities.	10.00%
Used to calculate ratio of written premium to surplus	times 1.25
Net gross premiums to surplus ratio. Florida statute section 624.4095 requires net gross premiums times 1.25 not exceed this ratio.	10-to-1
Net written premiums to surplus ratio. Florida statute section 624.4095 requires net written premiums times 1.25 not exceed this ratio.	4-to-1

Accumulated Other Comprehensive Income, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Net unrealized gain on investments, before taxes	$ 128,600	$ 164,500
Deferred tax expense	(45,000)	(57,600)
Total accumulated other comprehensive income, net	$ (83,600)	$ (106,900)

- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References + Details

Employee Benefit and Retirement Plans Employee Benefit and Retirement Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Employee Benefit and Retirement Plans [Abstract]
Safe habor matching, 100%	100.00%
Employee contributions, 100% match, percentage	3.00%
Safe harbor matching 50%	50.00%
Employee contributions 50% match, percentage	3.00%
Employee contributions, maximum match, percentage	5.00%
Company's contributions to Employers 401(k)	$ 1.8	$ 1.7	$ 1.2

Earnings Per Share Earnings Per Share (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Net income	$ 26,700	$ 24,500	$ 29,200	$ 14,000	$ 29,100	$ 15,200	$ 45,600	$ 10,800	$ 94,400	$ 100,700	$ 63,800
Weighted average number of shares outstanding - basic									32,070,911	31,529,621	31,142,534
Effect of diluted securities:									490,542	539,448	795,633
Weighted average number of shares outstanding - diluted									32,561,453	32,069,069	31,938,167
Employee Stock Option [Member]
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Effect of diluted securities:									286,764	223,811	464,334
Performance shares units [Member]
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Effect of diluted securities:									155,768	264,511	177,040
Restricted stock units (RSUs)
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Effect of diluted securities:									48,010	51,126	154,259

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Earnings Per Share Antidilutive Securities (Details) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of EPS	257,405	260,171	162,800
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of EPS	20,200	173,247	0

Selected Quarterly Financial Data Selected Quarterly Financial Data (Details) - USD ($)
$ / shares in Units, $ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2015

Sep. 30, 2015

Jun. 30, 2015

Mar. 31, 2015

Dec. 31, 2014

Sep. 30, 2014

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Condensed Financial Statements, Captions [Line Items]

Prior Year Claims and Claims Adjustment Expense

$ 8,500

$ (7,200)

$ 4,600

$ 7,000

Net premiums earned

181,800

$ 179,000

$ 170,600

$ 159,000

$ 172,600

$ 172,100

$ 172,600

$ 167,200

690,400

684,500

642,300

Net realized (losses) gains on investments

(15,800)

2,000

1,900

1,200

2,000

1,800

9,200

3,300

(10,700)

16,300

9,500

Losses and loss adjustment expenses

105,900

115,800

101,500

106,200

110,200

122,400

98,500

122,300

429,400

453,400

463,600

Commission expense

22,800

21,000

22,900

18,700

20,400

20,600

20,400

20,000

85,400

81,400

78,300

Underwriting and other operating expenses

37,600

31,600

32,500

33,500

30,900

31,900

33,100

33,300

135,200

129,100

125,300

Income tax expense (benefit)

(9,100)

5,900

4,100

1,300

2,000

1,300

5,000

5,900

(10,700)

Net income

$ 26,700

$ 24,500

$ 29,200

$ 14,000

$ 29,100

$ 15,200

$ 45,600

$ 10,800

$ 94,400

$ 100,700

$ 63,800

Earnings per common share (Note 18):

Basic

$ 0.83

$ 0.76

$ 0.91

$ 0.44

$ 0.92

$ 0.48

$ 1.45

$ 0.34

$ 2.94

$ 3.19

$ 2.05

Diluted

$ 0.82

$ 0.75

$ 0.90

$ 0.43

$ 0.91

$ 0.47

$ 1.42

$ 0.34

$ 2.90

$ 3.14

$ 2.00

Amortization of deferred gain

$ 11,400

$ 13,100

$ 14,600

Reserves reallocated to taxable years

$ 36,900

56,300

13,100

27,200

Change Due to Estimated Reserves Ceded Under the LPT Agreement [Member]

Condensed Financial Statements, Captions [Line Items]

Net income

$ 8,800

$ 6,400

$ 31,100

$ 19,000

Earnings per common share (Note 18):

Basic

$ 0.28

$ 0.20

$ 0.99

$ 0.61

Diluted

$ 0.27

$ 0.20

$ 0.97

$ 0.59

Amortization of deferred gain

$ 8,800

$ 6,400

^[1]

$ 31,100

^[1]

$ 19,000

^[1]

Change to Contingent Profit Commission [Member]

Condensed Financial Statements, Captions [Line Items]

Net income

$ 2,900

$ 2,600

$ 10,800

$ 4,300

Earnings per common share (Note 18):

Basic

$ 0.08

$ 0.34

$ 0.14

Diluted

$ 0.08

$ 0.34

$ 0.13

EPS, basic and diluted

$ 0.09

Amortization of deferred gain

$ 2,900

$ 2,600

$ 10,800

^[2]

$ 4,300

^[2]

Due to change in reserves for non-taxable periods

Condensed Financial Statements, Captions [Line Items]

Net income

$ 11,500

$ 15,300

$ 3,600

$ 7,400

Earnings per common share (Note 18):

Basic

$ 0.36

$ 0.48

$ 0.11

$ 0.24

Diluted

$ 0.35

$ 0.47

$ 0.11

$ 0.23

Effective Income Tax Rate Reconciliation, Percent

65.30%

15.40%

3.40%

13.90%

Condensed Financial Statements, Captions [Line Items]

Prior Year Claims and Claims Adjustment Expense

$ 9,000

Condensed Financial Statements, Captions [Line Items]

Prior Year Claims and Claims Adjustment Expense

500

$ 1,900

Condensed Financial Statements, Captions [Line Items]

Net income

$ 8,500

Earnings per common share (Note 18):

EPS, basic and diluted

$ 0.26

[1]	(1)The cumulative adjustments to the Deferred Gain were also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, so that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.
[2]	(1)The cumulative adjustments to the Deferred Gain were also recognized in losses and LAE incurred in the consolidated statement of comprehensive income, so that the Deferred Gain reflects the balance that would have existed had the revised reserves been recognized at the inception of the LPT Agreement.

Schedule II. Condensed Financial Information of Registrant (Condensed Balance Sheets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Excess tax benefits from stock-based compensation	$ 1,200	$ 1,200	$ 0
Investments
Investment in securities available-for-sale (amortized cost $108,890 in 2013 and $133,606 in 2012)	2,487,200	2,448,400
Equity securities at fair value (amortized cost $42,861 in 2013 and $30,678 in 2012)	198,700	172,700
Total investments	2,487,200	2,448,400
Cash and cash equivalents	56,600	103,600	34,500	$ 140,700
Restricted cash and cash equivalents	2,500	10,800
Deferred income taxes, net	67,900	49,700
Other assets	40,900	23,500
Total assets	3,755,800	3,769,700
Liabilities and stockholders’ equity
Accounts payable and accrued expenses	24,100	20,400
Notes payable	32,000	92,000
Other liabilities	40,500	36,700
Total liabilities	2,995,000	3,082,900
Stockholders’ equity:
Common stock, $0.01 par value; 150,000,000 shares authorized; 55,589,454 and 54,866,802 shares issued and 32,216,480 and 31,493,828 shares outstanding at December 31, 2015 and 2014, respectively	600	600
Preferred stock, $0.01 par value; 25,000,000 shares authorized; none issued	0	0
Additional paid-in capital	357,200	346,600
Retained earnings	682,000	595,300
Accumulated other comprehensive income, net	83,600	106,900
Treasury stock, at cost (23,372,974 shares at December 31, 2015 and 2014)	(362,600)	(362,600)
Total stockholders’ equity	760,800	686,800
Total liabilities and stockholders’ equity	3,755,800	3,769,700
Parent Company [Member]
Excess tax benefits from stock-based compensation	1,200	1,200	0
Investments
Investment in subsidiaries	647,100	567,100
Investment in securities available-for-sale (amortized cost $108,890 in 2013 and $133,606 in 2012)	42,200	86,700
Equity securities at fair value (amortized cost $42,861 in 2013 and $30,678 in 2012)	51,600	58,600
Total investments	740,900	712,400
Cash and cash equivalents	1,400	10,900	$ 6,400	$ 40,100
Restricted cash and cash equivalents	0	4,600
Intercompany receivable	200	300
Federal income taxes recoverable	1,700	6,600
Deferred income taxes, net	20,600	13,900
Other assets	1,500	1,900
Total assets	766,300	750,600
Liabilities and stockholders’ equity
Accounts payable and accrued expenses	5,200	3,800
Notes payable	0	60,000
Other liabilities	300	0
Total liabilities	5,500	63,800
Stockholders’ equity:
Common stock, $0.01 par value; 150,000,000 shares authorized; 55,589,454 and 54,866,802 shares issued and 32,216,480 and 31,493,828 shares outstanding at December 31, 2015 and 2014, respectively	600	600
Preferred stock, $0.01 par value; 25,000,000 shares authorized; none issued	0	0
Additional paid-in capital	357,200	346,600
Retained earnings	682,000	595,300
Accumulated other comprehensive income, net	83,600	106,900
Treasury stock, at cost (23,372,974 shares at December 31, 2015 and 2014)	(362,600)	(362,600)
Total stockholders’ equity	760,800	686,800
Total liabilities and stockholders’ equity	$ 766,300	$ 750,600

Schedule II. Condensed Financial Information of Registrant (Condensed Balance Sheets Parenthetical) (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fixed maturity securities, amortized cost	$ 2,358,600	$ 2,283,900
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	55,589,454	54,866,802
Common stock, shares outstanding (in shares)	32,216,480	31,493,828
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000
Preferred stock, shares issued (in shares)	0	0
Treasury stock, at cost (in shares)	23,372,974	23,372,974
Parent Company [Member]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000
Preferred stock, shares issued (in shares)	0	0
Debt Securities [Member]
Fixed maturity securities, amortized cost	$ 2,221,100	$ 2,186,100
Debt Securities [Member] \| Parent Company [Member]
Fixed maturity securities, amortized cost	40,200	83,300
Equity Securities [Member]
Fixed maturity securities, amortized cost	137,500	97,800
Equity Securities [Member] \| Parent Company [Member]
Fixed maturity securities, amortized cost	$ 46,800	$ 48,600

Schedule II. Condensed Financial Information of Registrant (Condensed Statements of Income) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues
Net investment income									$ 72,200	$ 72,400	$ 70,800
Realized gains on investments	$ (15,800)	$ 2,000	$ 1,900	$ 1,200	$ 2,000	$ 1,800	$ 9,200	$ 3,300	(10,700)	16,300	9,500
Total revenues									752,100	773,500	723,500
Expenses
Interest expense									2,700	3,000	3,200
Total expenses									652,700	666,900	670,400
Income tax expense (benefit)	(9,100)	5,900	4,100	4,100	1,300	1,300	2,000	1,300	5,000	5,900	(10,700)
Net income	$ 26,700	$ 24,500	$ 29,200	$ 14,000	$ 29,100	$ 15,200	$ 45,600	$ 10,800	$ 94,400	$ 100,700	$ 63,800
Earnings per common share for the stated periods (Note 18):
Basic	$ 0.83	$ 0.76	$ 0.91	$ 0.44	$ 0.92	$ 0.48	$ 1.45	$ 0.34	$ 2.94	$ 3.19	$ 2.05
Diluted	$ 0.82	$ 0.75	$ 0.90	$ 0.43	$ 0.91	$ 0.47	$ 1.42	$ 0.34	2.90	3.14	2.00
Cash dividends declared per common share									$ 0.24	$ 0.24	$ 0.24
Parent Company [Member]
Revenues
Net investment income									$ 4,000	$ 5,200	$ 6,000
Realized gains on investments									2,400	5,800	4,300
Total revenues									6,400	11,000	10,300
Expenses
Other operating expenses									13,800	13,500	12,000
Interest expense									1,100	1,400	1,600
Total expenses									14,900	14,900	13,600
Income (loss) before income taxes and equity in earnings of subsidiaries									(8,500)	(3,900)	(3,300)
Income tax expense (benefit)									(3,300)	(2,600)	(1,500)
Net income (loss) before equity in earnings of subsidiaries									(5,200)	(1,300)	(1,800)
Equity in net income of subsidiaries									99,600	102,000	65,600
Net income									$ 94,400	$ 100,700	$ 63,800
Earnings per common share for the stated periods (Note 18):
Basic									$ 2.94	$ 3.19	$ 2.05
Diluted									$ 2.90	$ 3.14	$ 2.00

Schedule II. Condensed Financial Information of Registrant (Condensed Statements of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating activities
Net income	$ 26,700	$ 24,500	$ 29,200	$ 14,000	$ 29,100	$ 15,200	$ 45,600	$ 10,800	$ 94,400	$ 100,700	$ 63,800
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Amortization expense									8,300	7,000	6,100
Realized gains on investments									10,700	(16,300)	(9,500)
Stock-based compensation									4,600	6,000	5,600
Excess Tax Benefit from Share-based Compensation, Operating Activities									1,200	1,200	0
Amortization of premium on investments, net									12,800	10,600	9,000
Deferred income tax expense									(5,600)	(500)	(10,800)
Change in operating assets and liabilities:
Accounts payable, accrued expenses and other liabilities									8,600	12,800	1,800
Federal income taxes									(3,900)	6,500	(3,700)
Other									(7,000)	(10,500)	(2,400)
Net cash provided by operating activities									116,400	171,900	166,500
Investing activities
Purchase of fixed maturity securities									(476,900)	(378,000)	(514,200)
Purchase of equity securities									(85,100)	(29,500)	(30,500)
Proceeds from sale of fixed maturity securities									105,400	47,900	52,500
Proceeds from maturities and redemptions of investments									323,900	251,100	206,800
Proceeds from sale of equity securities									34,700	36,500	30,700
Capital Contributions to subsidiary									0	0	(44,000)
Restricted cash used in investing activities									8,300	(4,200)	(1,200)
Net cash provided by investing activities									(101,200)	(86,700)	(260,100)
Financing activities
Cash transactions related to stock-based compensation									4,800	1,600	6,500
Dividends paid to stockholders									(7,700)	(7,600)	(7,500)
Payments on notes payable and capital leases									(60,500)	(11,300)	(11,600)
Excess tax benefits from stock-based compensation									1,200	1,200	0
Net cash used in financing activities									(62,200)	(16,100)	(12,600)
Net increase (decrease) in cash and cash equivalents									(47,000)	69,100	(106,200)
Cash and cash equivalents at the beginning of the period				103,600				34,500	103,600	34,500	140,700
Cash and cash equivalents at the end of the period	56,600				103,600				56,600	103,600	34,500
Parent Company [Member]
Operating activities
Net income									94,400	100,700	63,800
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Equity in net income of subsidiaries									99,600	102,000	65,600
Realized gains on investments									(2,400)	(5,800)	(4,300)
Stock-based compensation									4,600	6,000	5,600
Excess Tax Benefit from Share-based Compensation, Operating Activities									(1,200)	(1,200)	0
Amortization of premium on investments, net									900	1,000	1,300
Deferred income tax expense									(4,600)	(2,300)	(500)
Change in operating assets and liabilities:
Accounts payable, accrued expenses and other liabilities									1,700	1,200	(1,700)
Federal income taxes									4,900	800	(1,800)
Other assets									(400)	(900)	(200)
Intercompany payable/receivable									100	(1,400)	5,600
Other									(1,200)	(1,000)	0
Net cash provided by operating activities									400	(1,100)	2,600
Investing activities
Purchase of fixed maturity securities									(21,600)	(12,000)	(29,500)
Purchase of equity securities									(19,000)	(20,700)	(23,600)
Proceeds from sale of fixed maturity securities									18,300	4,100	35,500
Proceeds from maturities and redemptions of investments									45,500	32,600	17,600
Proceeds from sale of equity securities									24,000	20,600	15,500
Cash dividends received from subsidiaries									0	0	3,600
Restricted cash used in investing activities									4,600	(4,100)	(400)
Net cash provided by investing activities									51,800	20,500	(25,300)
Financing activities
Cash transactions related to stock-based compensation									4,800	1,500	6,500
Dividends paid to stockholders									(7,700)	(7,600)	(7,500)
Payments on notes payable and capital leases									(60,000)	(10,000)	(10,000)
Excess tax benefits from stock-based compensation									1,200	1,200	0
Net cash used in financing activities									(61,700)	(14,900)	(11,000)
Net increase (decrease) in cash and cash equivalents									(9,500)	4,500	(33,700)
Cash and cash equivalents at the beginning of the period				$ 10,900				$ 6,400	10,900	6,400	40,100
Cash and cash equivalents at the end of the period	$ 1,400				$ 10,900				$ 1,400	$ 10,900	$ 6,400

Schedule II. Condensed Financial Information of Registrant (Notes to Condensed Financial Statements) (Details) - USD ($)
$ in Thousands

3 Months Ended

12 Months Ended

Mar. 31, 2015

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Schedule of Available-for-sale Securities [Line Items]

Payments on notes payable

$ 60,500

$ 11,300

$ 11,600

Amortized Cost

Due in one year or less, amortized cost

113,600

Due after one year through five years, amortized cost

859,300

Due after five years through ten years, amortized cost

636,900

Due after ten years, amortized cost

252,400

Mortgage and asset-backed securities, amortized cost

358,900

Total, amortized cost

2,221,100

Estimated Fair Value

Due in one year or less, fair value

115,100

Due after one year through five years, fair value

884,500

Due after five years through ten years, fair value

657,100

Due after ten years, fair value

267,700

Mortgage and asset-backed securities, fair value

364,100

Total, fair value

2,288,500

2,275,700

Change in net unrealized gains on investments, net of taxes

(23,300)

16,500

(39,100)

Cash paid for interest

2,800

3,000

$ 3,300

Line of credit facility, decrease, repayments

60,000

Investments

2,487,200

$ 2,448,400

Parent Company [Member]

Amortized Cost

Due in one year or less, amortized cost

14,600

Due after one year through five years, amortized cost

15,600

Due after five years through ten years, amortized cost

3,300

Due after ten years, amortized cost

6,700

Total, amortized cost

40,200

Estimated Fair Value

Due in one year or less, fair value

14,900

Due after one year through five years, fair value

16,100

Due after five years through ten years, fair value

3,700

Due after ten years, fair value

7,500

Total, fair value

$ 42,200

Change in net unrealized gains on investments, net of taxes

$ 2,000

Employee Stock Option [Member]

Estimated Fair Value

Number of options or share units, granted

80,800

141,744

162,800

Number of outstanding options or share units

1,121,545

1,521,290

1,546,898

1,830,772

Restricted stock units (RSUs)

Estimated Fair Value

Number of options or share units, granted

112,048

87,396

84,215

Number of outstanding options or share units

319,033

306,867

358,346

406,262

Performance shares units [Member]

Estimated Fair Value

Number of outstanding options or share units

110,000

^[1]

125,340

^[2]

147,440

^[2]

Line of Credit [Member]

Estimated Fair Value

Cash paid for interest

$ 1,300

$ 1,400

$ 1,600

Line of Credit [Member] | Parent Company [Member]

Estimated Fair Value

Cash paid for interest

$ 1,300

$ 1,400

$ 1,600

[1]	The PSUs awarded in March 2015 were awarded to certain officers of the Company and have a performance period of two years followed by an additional one year vesting period. The PSU awards are subject to certain performance goals with payouts that range from 0% to 200% of the target awards. The value shown in the table represents the aggregate number of PSUs awarded at the target level.
[2]	The PSUs granted in 2013 and 2014 have a performance period of three years and are subject to certain performance goals, based on the Company's statutory combined ratio, with payouts that range from 0% to 200% of the target awards. The ultimate payout of the PSUs awarded in 2013 was 0% of the target award.

Schedule VI. Supplemental Information (Details) - USD ($) $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Supplemental Information for Property, Casualty Insurance Underwriters [Abstract]
Deferred policy acquisition costs	$ 44,300				$ 44,600					$ 44,300	$ 44,600	$ 43,500
Unpaid losses and loss adjustment expenses	2,347,500				2,369,700					2,347,500	2,369,700	2,330,500	$ 2,231,500
Unearned premiums	308,900				310,800					308,900	310,800	304,000
Net premiums earned	$ 181,800	$ 179,000	$ 170,600	$ 159,000	$ 172,600	$ 172,100	$ 172,600	$ 167,200		690,400	684,500	642,300
Net investment income										72,200	72,400	70,800
Current year										456,900	503,800	494,500
Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense Including LPT Amortization and Adj										(27,600)	(50,500)	(31,000)
Deferred policy acquisition cost, amortization expense										103,900	102,700	96,900
Payments For Losses And Loss Adjustment Expense Including LPT Amortization and Adj										410,200	340,600	302,300
Premiums written, net									$ 678,500	$ 689,300	$ 687,600	$ 678,500

Consolidated Stockholders Equity (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stockholders Equity Parenthetical [Abstract]
Change in net unrealized gains on investments, net of tax of	$ (12,600)	$ 8,900	$ (21,000)

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2015
Stockholders' Equity Attributable to Parent [Abstract]
Treasury Stock	Stockholders' Equity Stock Repurchase Programs Since the Company's initial public offering in January 2007 through December 31, 2015, the Company repurchased a total of 23,372,974 shares of common stock at an average cost per share of $15.51, which is reported as treasury stock, at cost, on the accompanying consolidated balance sheets. There were no stock repurchase programs authorized by the Board of Directors as of December 31, 2015.

Subsequent Events (Details) $ in Millions	12 Months Ended
Subsequent Events (Details) $ in Millions	Dec. 31, 2015 USD ($)
Subsequent Events [Abstract]
Stock Repurchase Program, Authorized Amount	$ 50.0
Stock Repurchase Program Expiration Date	Feb. 22, 2018

Fair Value of Financial Instruments, Fair Value Inputs (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	$ 2,487.2	$ 2,448.4
Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	2,288.5	2,275.7
Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	2,288.5	2,275.7
Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
US Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	120.2	166.7
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	120.2	166.7
US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	24.4	39.6
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	24.4	39.6
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
US States and Political Subdivisions Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	854.5	745.8
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	854.5	745.8
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	925.3	908.3
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	925.3	908.3
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	237.9	288.4
Residential Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Residential Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	237.9	288.4
Residential Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Commercial Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	80.3	65.4
Commercial Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Commercial Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	80.3	65.4
Commercial Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Asset-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	45.9	61.5
Asset-backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Asset-backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	45.9	61.5
Asset-backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	198.7	172.7
Equity Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	198.7	172.7
Equity Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0.0	0.0
Equity Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	$ 0.0	$ 0.0