0001379041-24-000146 | 10-Q | XBRL Viewer

Basis of Presentation	6 Months Ended
Basis of Presentation	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business Description and Basis of Presentation	Basis of Presentation and Summary of Operations 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), Employers Assurance Company (EAC), and Cerity Insurance Company (CIC), 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. In 1999, the Nevada State Industrial Insurance System (the Fund) entered into a retroactive 100% quota share reinsurance agreement (the LPT Agreement) through a loss portfolio transfer transaction with third party reinsurers. The LPT Agreement, which ceded to the reinsurers substantially all of the Fund's outstanding losses as of June 30, 1999 for claims with original dates of injury prior to July 1, 1995, provides coverage for losses up to $2.0 billion, excluding losses for burial and transportation expenses. The LPT Agreement will remain in effect until: (i) all claims under the covered policies have closed; (ii) the LPT Agreement is commuted or terminated, upon the mutual agreement of the parties; or (iii) the reinsurers’ aggregate maximum limit of liability is exhausted, whichever occurs first. The LPT Agreement does not provide for any additional termination terms. On January 1, 2000, EICN assumed all of the assets, liabilities and operations of the Fund, including the Fund’s rights and obligations associated with the LPT Agreement (See Note 9). The Company accounts for the LPT Agreement as retroactive reinsurance. Upon entry into the LPT Agreement, an initial deferred reinsurance gain (the Deferred Gain) was recorded as a liability on the Company’s Consolidated Balance Sheets. The Company is also entitled to receive a contingent profit commission under the LPT Agreement through June 30, 2024. The contingent profit commission is estimated based on both actual paid results to date and projections of expected paid losses under the LPT Agreement and is recorded as an asset on the Company’s Consolidated Balance Sheets. The Contingent Commission receivable at June 30, 2024 was $14.6 million. The accompanying consolidated financial statements have been prepared in accordance with United States (U.S.) generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X of the Securities Exchange Act of 1934 (Exchange Act), as amended. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal, recurring adjustments) necessary for a fair presentation of the Company’s consolidated financial position and results of operations for the periods presented have been included. The results of operations for an interim period are not necessarily indicative of the results for an entire year. These financial statements have been prepared consistent with the accounting policies described in the Company’s Form 10-K for the year ended December 31, 2023 (Annual Report). The Company operates as a single operating segment, Insurance Operations, through its wholly owned subsidiaries. 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 (CODM) to make decisions about resources to be allocated to the segment and assess its performance based on discrete financial information. Prior to December 31, 2023, the Company operated through two reportable segments: Employers and Cerity. All periods prior to December 31, 2023 have been conformed to the current presentation. Detailed financial information about the Company's single operating segment is presented in Note 14. 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, recoverability of deferred income taxes, and valuation of investments.

Notes Payable	6 Months Ended
Notes Payable	Jun. 30, 2024
Notes Payable [Abstract]
Debt Disclosure [Text Block]	Financing Arrangements Credit Agreement On May 28, 2024, EHI entered into a Credit Agreement (the Credit Agreement) with Wells Fargo Bank, National Association, as both administrative agent and issuing lender. The Credit Agreement provides for a $25.0 million, unsecured, three-year revolving credit facility and is guaranteed by certain of EHI’s wholly owned subsidiaries, Employers Group, Inc. (EGI) and Cerity Group, Inc. (CGI). Borrowings under the Credit Agreement may be used for working capital and general corporate purposes of EHI and its subsidiaries. Pursuant to the terms of the Credit Agreement, EHI has an option to request an increase of the credit available under the facility up to a maximum facility amount of $35.0 million, subject to the consent of the lender(s) and the satisfaction of certain conditions. The interest rates applicable to loans under the Credit Agreement are generally based on either, at EHI's option: (i) a base rate, defined as the higher of the Prime Rate, the Federal Funds Rate plus 1.25% and the Adjusted Term Secured Overnight Financing Rate (SOFR) for a one-month tenor plus 1.75%, or (ii) an Adjusted Term SOFR Rate plus 1.75% In addition, EHI is subject to a fee on the lender’s unused commitment, ranging from 0.30% to 0.55%. The applicable margin and the amount of such commitment fee vary based upon the financial strength rating of EHI’s insurance subsidiaries as most recently announced by A.M. Best or EHI’s debt to total capitalization ratio if such financial strength rating is not available. Interest paid and/or fees incurred pursuant to the Credit Agreement, as applicable, was less than $0.1 million for the three months ended June 30, 2024. The Credit Agreement contains covenants that require EHI and its consolidated subsidiaries to maintain: (i) a minimum consolidated net worth, defined as EHI’s total stockholders’ equity excluding any accumulated other comprehensive income or loss, of no less than $800.0 million; and (ii) a debt to total capitalization ratio of no more than 35%, in each case as determined in accordance with the Credit Agreement. As of June 30, 2024, EHI has remained in compliance with all of the covenants associated with the Credit Agreement since its inception. EHI incurred $0.2 million in debt issuance costs in connection with the Credit Agreement, which are being amortized over the three-year life in Interest and financing expenses on the Company's Consolidated Statements of Comprehensive Income (Loss). The annual commitment fee on the unused portion of the facility is 0.35%, for a maximum of $87,500. Advances can be repaid at any time without prepayment penalties or additional fees. EHI had no borrowings under the Credit Agreement during the three months ended June 30, 2024. FHLB All of the Company's insurance subsidiaries are members of the FHLB. Membership allows the insurance subsidiaries access to collateralized advances, which may be used to support and enhance liquidity management. The amount of advances that may be taken is dependent on statutory admitted assets on a per company basis. FHLB membership also allows the Company’s insurance subsidiaries access to standby letters of credit (Letter of Credit Agreements). Letter of Credit Agreements issued must be fully secured with eligible collateral at all times and are subject to annual maintenance charges and a fee of 15 basis points on issued amounts. As of both June 30, 2024 and December 31, 2023, letters of credit totaling $70.0 million, were issued in lieu of securities on deposit with the State of California under these Letter of Credit Agreements. The Letter of Credit Agreements currently in effect expire on March 31, 2025, and will remain evergreen with automatic one-year extensions unless the FHLB notifies the beneficiary at least 60 days prior to the then applicable expiration date of its election not to renew. As of June 30, 2024 and December 31, 2023, investment securities having a fair value of $265.2 million and $286.4 million, respectively, were pledged to the FHLB by the Company’s insurance subsidiaries in support of the collateralized advance facility and the Letter of Credit Agreements.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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+ Details

Notes Payable Letters of Credit (Details) - USD ($)	3 Months Ended		6 Months Ended
Notes Payable Letters of Credit (Details) - USD ($)	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Letters of Credit Facilities [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 25,000,000		$ 25,000,000
Line of Credit Facility, Interest Rate at Period End	1.25%		1.25%
Debt Instrument, Interest Rate, Stated Percentage	1.75%		1.75%
Line of Credit Facility, Commitment Fee Percentage	0.35%
Interest and financing expenses		$ 1,900,000		$ 4,200,000
Debt Issuance Costs, Gross	$ 200,000		$ 200,000
Repayments of FHLBank Advance, Investing Activities			0	$ 76,800,000
Line of Credit Facility, Fair Value of Amount Outstanding	0		0
Line of Credit Facility, Periodic Payment, Interest	100,000
Maximum [Member]
Letters of Credit Facilities [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 35,000,000		$ 35,000,000
Line of Credit Facility, Interest Rate at Period End	0.55%		0.55%
Debt Instrument, Interest Rate, Stated Percentage	1.75%		1.75%
Line of Credit Facility, Commitment Fee Amount	$ 87,500
Line of Credit Facility, Covenant Terms			a debt to total capitalization ratio of no more than 35%, in each case as determined in accordance with the Credit Agreement. As of June 30, 2024, EHI has remained in compliance with all of the covenants associated with the Credit Agreement since its inception.
Minimum [Member]
Letters of Credit Facilities [Line Items]
Line of Credit Facility, Interest Rate at Period End	0.30%		0.30%
Debt Instrument, Covenant Description			(i) a minimum consolidated net worth, defined as EHI’s total stockholders’ equity excluding any accumulated other comprehensive income or loss, of no less than $800.0 million; and
Federal Home Loan Bank [Member]
Letters of Credit Facilities [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 70,000,000.0		$ 70,000,000.0		$ 70,000,000.0
Letters of credit collateral amount	$ 265,200,000		$ 265,200,000		$ 286,400,000
Letters of credit, unused capacity, commitment fee percentage			15.00%

Investments Other Invested Assets (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Other Invest Assets [Abstract]
Other invested assets at NAV	$ 97.5	$ 91.5
Investment Owned, at Cost	86.5	82.5
Total other invested assets	$ 97.5	$ 91.5

- Definition

Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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- Definition

Cost of the investment.

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+ Details

Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Investments:
Fixed maturity securities at fair value (amortized cost $2,136.6 at June 30, 2024 and $2,048.0 at December 31, 2023, less CECL allowance of $1.9 at June 30, 2024 and $2.7 at December 31, 2023)	$ 2,009.4	$ 1,936.3
Equity securities at fair value (cost $134.4 at June 30, 2024 and $125.9 at December 31, 2023)	232.6	211.2
Equity securities at cost	5.7	6.0
Other invested assets (cost $86.5 at June 30, 2024 and $82.5 at December 31, 2023)	97.5	91.5
Short-term investments at fair value (amortized cost $30.9 at June 30, 2024 and $33.1 at December 31, 2023)	30.9	33.1
Total investments	2,376.1	2,278.1
Cash and cash equivalents	95.5	226.4
Restricted cash and cash equivalents	0.2	0.2
Accrued investment income	16.7	16.3
Premiums receivable (less CECL allowance of $18.8 at June 30, 2024 and $17.9 at December 31, 2023)	399.8	359.4
Reinsurance recoverable for:
Paid losses	6.3	6.3
Unpaid losses (less CECL allowance of $0.9 at June 30, 2024 and $0.9 at December 31, 2023)	417.4	427.5
Deferred policy acquisition costs	62.3	55.6
Deferred income tax asset, net	42.1	43.4
Property and equipment, net	6.7	6.5
Operating lease right-of-use assets	4.4	5.1
Intangible assets, net	13.6	13.6
Goodwill	36.2	36.2
Contingent commission receivable—LPT Agreement	14.6	14.2
Cloud computing arrangements	21.2	28.0
Other assets	36.9	33.6
Total assets	3,550.0	3,550.4
Liabilities and stockholders’ equity
Unpaid losses and loss adjustment expenses	1,850.9	1,884.5
Unearned premiums	419.4	379.7
Commissions and premium taxes payable	65.2	66.0
Accounts payable and accrued expenses	18.7	26.1
Deferred reinsurance gain—LPT Agreement	95.3	99.2
Operating lease liability	5.1	5.9
Non-cancellable obligations	12.1	17.0
Other liabilities	60.4	58.1
Total liabilities	2,527.1	2,536.5
Commitments and contingencies
Stockholders’ equity:
Common stock, $0.01 par value; 150,000,000 shares authorized; 58,167,193 and 58,055,968 shares issued and 24,896,116 and 25,369,753 shares outstanding at June 30, 2024 and December 31, 2023, respectively	0.6	0.6
Preferred stock, $0.01 par value; 25,000,000 shares authorized; none issued	0.0	0.0
Additional paid-in capital	420.9	419.8
Retained earnings	1,429.4	1,384.3
Accumulated other comprehensive loss, net of tax	(99.0)	(86.0)
Treasury stock, at cost (33,271,077 shares at June 30, 2024 and 32,686,215 shares at December 31, 2023)	(729.0)	(704.8)
Total stockholders’ equity	1,022.9	1,013.9
Total liabilities and stockholders’ equity	$ 3,550.0	$ 3,550.4

Earnings Per Share (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Earnings Per Share (Details) - USD ($) $ in Millions	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Net income available to stockholders - basic and diluted	$ 31.7	$ 34.9	$ 60.0	$ 58.5
Weighted average number of shares outstanding - basic	25,278,473	26,691,652	25,312,208	26,932,897
Effect of dilutive securities:
Dilutive securities	85,468	111,688	137,749	163,772
Weighted average number of shares outstanding - diluted	25,363,941	26,803,340	25,449,957	27,096,669
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	82,072	77,252	41,036	38,626
Performance Shares [Member]
Effect of dilutive securities:
Dilutive securities	47,684	85,691	81,353	113,469
Stock Option [Member]
Effect of dilutive securities:
Dilutive securities	0	0	0	4,143
Restricted Stock Units (RSUs) [Member]
Effect of dilutive securities:
Dilutive securities	37,784	25,997	56,396	46,160

Stock-Based Compensation

6 Months Ended

Jun. 30, 2024

Stock-Based Compensation [Abstract]

Stock-Based compensation

Stock-Based Compensation

The Company awarded restricted stock units (RSUs) and performance share units (PSUs) to certain employees and non-employee Directors of the Company as follows:


	Number Awarded	Weighted Average Fair Value on Date of Grant	Aggregate Fair Value on Date of Grant
			(in millions)
February 2024
RSUs(1)	61,280	46.36	2.8
PSUs(2)	77,360	46.36	3.6

March 2024
RSUs(1)	4,712	45.00	0.2

May 2024


RSUs(3)	17,052	40.00	0.7

(1)These RSUs were awarded to certain employees of the Company on two separate dates and all vest 25% on March 15, 2025 and each of the subsequent three anniversaries of that date.

(2)These PSUs were awarded to certain employees of the Company and have a performance period of three years. The PSU awards are subject to certain performance goals with payouts that range from 0% to 250% of the target awards. The value shown in the table represents the aggregate number of PSUs awarded at the target level.

(3)All RSUs awarded on this date were awarded to non-employee directors of the Company and vest in full on May 23, 2025.

Employees who are awarded RSUs and PSUs are entitled to receive dividend equivalents for eligible awards, payable in cash, when and if, the underlying award vests and becomes payable. If the underlying award does not vest or is forfeited, dividend equivalents with respect to the underlying award fail to become payable and are forfeited.

RSUs and PSUs are subject to accelerated vesting in certain circumstances, including but not limited to: death, disability, retirement, or in connection with a change of control of the Company.

As of June 30, 2024, the Company no longer had any stock options outstanding. During the six months ended June 30, 2023, and the year ended December 31, 2023, there were 23,500 stock options exercised.

As of June 30, 2024, the Company had 231,821 RSUs and 202,494 PSUs (based on the target achievement for the PSUs awarded) outstanding.

New Accounting Standards	6 Months Ended
New Accounting Standards	Jun. 30, 2024
New Accounting Standards [Abstract]
New Accounting Standards	New Accounting Standards Recently Issued Accounting Standards In November 2023, the Financial Accounting Standards Board (FASB) issued ASU 2023-07, Segment Reporting (Topic 280). The amendments in this update improve disclosures about reportable segments and provide more detailed information about a reportable segment's expenses. Specifically, the amendments in this update require that a public entity disclose, on an annual and interim basis: (i) significant segment expenses that are regularly provided to the CODM; (ii) an amount for other segment items by reportable segment and a description on their composition; (iii) all annual disclosures about a reportable segment's profit or loss and assets currently required by Topic 280 in interim periods; (iv) the measures the CODM uses in assessing performance and allocating resources; and (v) the title and position of the CODM. Public entities that have a single reporting segment are also required to provide all the disclosures required by this amendment, along with all existing segment disclosures in Topic 280. This update is effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. The Company will adopt this standard when it becomes effective. Recently Adopted Accounting Standards In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740). This update requires public business entities to annually disclose specific categories within the income tax rate reconciliation, and provide additional information for reconciling items that meet a certain quantitative threshold. Additionally, the amendments in this update require entities to disclose certain information about income taxes paid, income tax disaggregation, disclosures around unrecognized tax benefits, and the removal of disclosures related to temporary differences surrounding deferred tax liabilities to enhance the transparency and decision usefulness of income tax disclosures. This update is effective for fiscal years beginning after December 15, 2024 and early adoption is permitted for financial statements that have not been issued. The Company early adopted this update as of December 31, 2023, and the impact of this standard was not material to its consolidated financial condition or its results of operations. In March 2020, the FASB issued Accounting Standards Update (ASU) 2020-04, Reference Rate Reform (Topic 848). This update provided optional transition guidance to ease the potential accounting burden associated with transitioning away from the London Interbank Offered Rate (LIBOR), with optional expedients and exceptions related to the application of US GAAP to contracts, hedging relationships and other transactions affected by reference rate reform. Companies can elect to adopt this ASU through December 31, 2024. The Company has determined that there was no impact of LIBOR transitioning on its existing contracts and investments.

- Definition

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

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+ Details

Segment Reporting

6 Months Ended

Jun. 30, 2024

Segment Reporting [Abstract]

Segment Reporting Disclosure [Text Block]

Segment Reporting

The Company operates as a single reportable segment, Insurance Operations, through its wholly owned subsidiaries. In the fourth quarter of 2023, the Company developed and executed an integration plan to consolidate its previously segregated direct-to-consumer operations (Cerity) into the Company's mainstream operations, while retaining its digital distribution capabilities. The integration plan, which will allow the Company to operate more efficiently and generate cost savings, resulted in a change in the composition of our reportable segments by eliminating any distinction for reporting purposes, including stand-alone financial statements, among our former segments, which were: Employers and Cerity.

The Insurance Operations segment represents the traditional business offered through its agents, including business originated from the Company's strategic partnerships and alliances and also direct-to-customer business.

The following table summarizes the Company's written premium and components of net income. The prior period has been conformed to current presentation.


	Insurance Operations		Total
	(in millions)
Three Months Ended June 30, 2024
Gross premiums written	$	207.9	$	207.9
Net premiums written	206.1		206.1

Net premiums earned	187.8		187.8
Net investment income	26.9		26.9
Net realized and unrealized gains on investments	2.2		2.2

Other income	0.1		0.1
Total revenues	217.0		217.0

Losses and loss adjustment expenses	108.8		108.8
Commission expense	26.8		26.8
Underwriting and general and administrative expenses	41.4		41.4


Total expenses	177.0		177.0

Net income before income taxes	40.0		40.0
Income tax expense	8.3		8.3
Net income	$	31.7	$	31.7

Three Months Ended June 30, 2023
Gross premiums written	$	198.4	$	198.4
Net premiums written	196.6		196.6

Net premiums earned	177.1		177.1
Net investment income	26.8		26.8
Net realized and unrealized gains on investments	11.3		11.3


Total revenues	215.2		215.2

Losses and loss adjustment expenses	90.5		90.5
Commission expense	23.6		23.6
Underwriting and general and administrative expenses	46.0		46.0
Interest and financing expenses	1.9		1.9
Other expenses	9.4		9.4
Total expenses	171.4		171.4

Net income before income taxes	43.8		43.8
Income tax expense	8.9		8.9
Net income	$	34.9	$	34.9


	Insurance Operations		Total
	(in millions)
Six Months Ended June 30, 2024
Gross premiums written	$	418.7	$	418.7
Net premiums written	415.2		415.2

Net premiums earned	372.6		372.6
Net investment income	53.8		53.8
Net realized and unrealized gains on investments	13.6		13.6

Other income	0.1		0.1
Total revenues	440.1		440.1

Losses and loss adjustment expenses	225.3		225.3
Commission expense	52.3		52.3
Underwriting and general and administrative expenses	87.2		87.2


Total expenses	364.8		364.8

Net income before income taxes	$	75.3	$	75.3
Income tax expense	15.3		15.3
Net income	$	60.0	$	60.0


Six Months Ended June 30, 2023
Gross premiums written	$	393.3	$	393.3
Net premiums written	389.7		389.7

Net premiums earned	349.8		349.8
Net investment income	54.4		54.4
Net realized and unrealized gains on investments	17.7		17.7

Other income (loss)	(0.2)		(0.2)
Total revenues	421.7		421.7

Losses and loss adjustment expenses	197.9		197.9
Commission expense	47.1		47.1
Underwriting and general and administrative expenses	90.3		90.3
Interest and financing expenses	4.2		4.2
Other expenses	9.4		9.4
Total expenses	348.9		348.9

Net income before income taxes	72.8		72.8
Income tax expense	14.3		14.3
Net income	$	58.5	$	58.5

Entity-Wide Disclosures

The Company operates solely within the U.S. and does not have revenue from transactions with a single policyholder accounting for 10% or more of its revenues.

In-force premiums represent the estimated annual premium on all policies that are active and in-force on such date. More specifically, in-force premiums include policy endorsements but exclude estimated final audit premiums. When adjusting for estimated final audit premium, our total in-force premiums were $769.3 million, $729.5 million, $684.6 million, and $654.0 million as of June 30, 2024, December 31, 2023, June 30, 2023, and December 31, 2022, respectively. The Company's management focuses on in-force premium because it represents premium that is available for renewal in the future. The

following table shows our in-force premiums, in-force premiums including estimated final audit premium, and number of policies in-force for each of our largest states and all other states combined for the periods presented:


	June 30, 2024			December 31, 2023			June 30, 2023			December 31, 2022
State	In-force Premiums		Policies In-force	In-force Premiums		Policies In-force	In-force Premiums		Policies In-force	In-force Premiums		Policies In-force
	(dollars in millions)
California	$	328.0	43,965	$	311.5	43,353	$	291.0	43,133	$	279.7	42,876
Florida	58.0		10,490	56.6		10,008	53.0		9,790	49.4		9,417
New York	34.9		7,913	31.9		7,603	30.6		7,552	27.3		7,497


Other (43 states and D.C.)	308.4		66,154	294.6		65,445	278.8		64,373	266.1		61,566
Total in-force	$	729.3	128,522	$	694.6	126,409	$	653.4	124,848	$	622.5	121,356
Estimated audit premium	40.0		—	34.9		—	31.2		—	31.5		—
Total in-force, including estimated audit premium	$	769.3	128,522	$	729.5	126,409	$	684.6	124,848	$	654.0	121,356

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-41

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-21

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-21

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

+ Details

Consolidated Statements of Stockholders Equity (Parentheticals) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Statement of Stockholders' Equity [Abstract]
Change in net unrealized (losses) gains on investments, net of tax	$ 0.7	$ 4.1	$ 3.5	$ (2.3)

- Definition

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-12

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482765/220-10-50-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481694/830-30-45-17

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 20
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481694/830-30-45-20

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(19))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-10

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482659/740-20-45-11

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(21))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(23))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482659/740-20-45-2

+ Details

Exit and Disposal Cost (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Exit and Disposal Cost (Details) - USD ($) $ in Millions	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Property, Plant and Equipment [Abstract]
Business Exit Costs	$ 7.6
Asset Impairment Charges	2.6	$ 0.0	$ 2.6
Other General Expense	0.2
Gain (Loss) on Termination of Lease	$ 1.0	$ 0.0	$ 1.0

Investments

6 Months Ended

Jun. 30, 2024

Investments [Abstract]

Investments

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the Company’s available-for-sale (AFS) investments were as follows:


	Amortized Cost		Allowance for Current Expected Credit Losses		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
	(in millions)
At June 30, 2024
Fixed maturity securities
U.S. Treasuries	$	70.4	$	—	$	0.2	$	(3.0)	$	67.6
U.S. Agencies	2.3		—		—		(0.1)		2.2
States and municipalities	189.2		—		1.6		(5.8)		185.0
Corporate securities	1,004.1		(0.7)		4.0		(65.7)		941.7
Residential mortgage-backed securities	424.3		—		0.4		(45.4)		379.3
Commercial mortgage-backed securities	70.4		(0.4)		—		(5.6)		64.4
Asset-backed securities	180.7		(0.2)		0.9		(4.2)		177.2
Collateralized loan obligations	63.6		—		—		(0.1)		63.5
Foreign government securities	12.7		—		—		(2.9)		9.8
Other securities(1)	118.9		(0.6)		0.8		(0.4)		118.7
Total fixed maturity securities	$	2,136.6	$	(1.9)	$	7.9	$	(133.2)	$	2,009.4
Short-term investments	30.9		—		—		—		30.9
Total AFS investments	$	2,167.5	$	(1.9)	$	7.9	$	(133.2)	$	2,040.3


At December 31, 2023
Fixed maturity securities
U.S. Treasuries	$	60.3	$	—	$	0.6	$	(2.5)	$	58.4
U.S. Agencies	2.2		—		—		(0.1)		2.1
States and municipalities	212.3		—		3.1		(5.2)		210.2
Corporate securities	952.8		(2.1)		8.3		(63.2)		895.8
Residential mortgage-backed securities	399.3		—		0.9		(38.0)		362.2
Commercial mortgage-backed securities	70.2		—		—		(6.4)		63.8
Asset-backed securities	131.8		—		1.0		(4.8)		128.0
Collateralized loan obligations	92.2		—		—		(0.7)		91.5
Foreign government securities	12.7		—		—		(2.3)		10.4
Other securities(1)	114.2		(0.6)		1.0		(0.7)		113.9
Total fixed maturity securities	$	2,048.0	$	(2.7)	$	14.9	$	(123.9)	$	1,936.3
Short-term investments	33.1		—		—		—		33.1
Total AFS investments	$	2,081.1	$	(2.7)	$	14.9	$	(123.9)	$	1,969.4

(1)Other securities within fixed maturity securities consist of bank loans, which are classified as AFS and reported at fair value.

The cost and estimated fair value of the Company’s equity securities recorded at fair value at June 30, 2024 and December 31, 2023 were as follows:


	Cost		Estimated Fair Value
	(in millions)
At June 30, 2024
Equity securities at fair value
Industrial and miscellaneous	$	111.5	$	202.5
Other	22.9		30.1
Total equity securities at fair value	$	134.4	$	232.6




At December 31, 2023
Equity securities at fair value
Industrial and miscellaneous	$	104.4	$	181.7
Other	21.5		29.5
Total equity securities at fair value	$	125.9	$	211.2

The Company had Other invested assets totaling $97.5 million and $91.5 million (initial cost of $86.5 million and $82.5 million) at June 30, 2024 and December 31, 2023, respectively, consisting of private equity limited partnerships, which are carried at NAV based on information provided by the general partner. These investments are non-redeemable until conversion and are periodically evaluated by the Company for impairment based on the ultimate recovery of the investment. Changes in the value of these investments are recorded through Net realized and unrealized gains or losses on the Company’s Consolidated Statements of Comprehensive Income (Loss).

The amortized cost and estimated fair value of the Company’s fixed maturity securities at June 30, 2024, 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	$	46.3	$	45.6
Due after one year through five years	644.6		622.5
Due after five years through ten years	613.0		571.7
Due after ten years	93.7		85.2
Mortgage and asset-backed securities	739.0		684.4
Total	$	2,136.6	$	2,009.4

The following is a summary of AFS 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 in each case as of June 30, 2024 and December 31, 2023.


	June 30, 2024					December 31, 2023
	Estimated Fair Value		Gross Unrealized Losses		Number of Issues	Estimated Fair Value		Gross Unrealized Losses		Number of Issues
	(dollars in millions)
Less than 12 months:
Fixed maturity securities
U.S. Treasuries	$	20.1	$	(0.1)	7	$	11.9	$	(0.1)	5

States and municipalities	33.0		(0.5)		13	39.5		(0.3)		15
Corporate securities	134.6		(1.4)		36	26.1		(0.8)		13
Residential mortgage-backed securities	42.4		(0.3)		25	15.8		(0.2)		15

Asset-backed securities	66.3		(0.4)		22	24.0		(0.1)		15
Collateralized loan obligations	—		—		—	—		—		—

Other securities	23.3		(0.3)		117	12.6		(0.1)		70
Total fixed maturity securities	319.7		(3.0)		220	129.9		(1.6)		133

Total less than 12 months	$	319.7	$	(3.0)	220	$	129.9	$	(1.6)	133

12 months or greater:
Fixed maturity securities
U.S. Treasuries	$	34.8	$	(2.9)	11	$	23.7	$	(2.4)	7
U.S. Agencies	2.2		(0.1)		1	2.2		(0.1)		1
States and municipalities	83.6		(5.3)		36	73.5		(4.9)		32
Corporate securities	666.7		(64.3)		282	684.5		(62.4)		331
Residential mortgage-backed securities	293.6		(45.1)		234	306.6		(37.8)		228
Commercial mortgage-backed securities	52.5		(5.6)		23	53.0		(6.4)		24
Asset-backed securities	48.6		(3.8)		36	47.0		(4.7)		29
Collateralized loan obligations	5.4		(0.1)		3	80.5		(0.7)		21
Foreign government securities	9.8		(2.9)		2	10.4		(2.3)		2
Other securities	3.0		(0.1)		22	10.2		(0.6)		58
Total fixed maturity securities	1,200.2		(130.2)		650	1,291.6		(122.3)		733
Total 12 months or greater	$	1,200.2	$	(130.2)	650	$	1,291.6	$	(122.3)	733

As of June 30, 2024 and December 31, 2023, the Company had an allowance for current expected credit losses (CECL) on AFS investments of $1.9 million and $2.7 million, respectively (See Note 5). Those fixed maturity securities whose total fair value was less than amortized cost at each of June 30, 2024 and December 31, 2023, were those in which the Company had no intent, need or requirement to sell at an amount less than their amortized cost.

Realized gains and losses on investments include the gain or loss on a security at the time of sale compared to its original or adjusted cost (equity securities and other invested assets) or amortized cost (fixed maturity securities). Realized losses on fixed maturity securities are also recognized when securities are written down as a result of an other-than-temporary impairment or for unfavorable changes in CECL. Reversals of previously recognized realized losses on fixed maturity securities can also result when securities are written up for favorable changes in CECL.

Net realized gains and losses on investments and the change in unrealized gains and losses on the Company’s investments recorded at fair value are determined on a specific-identification basis and were as follows:


	Gross Realized Gains		Gross Realized Losses		Net Decrease in CECL Allowance		Change in Net Unrealized Gains (Losses)		Changes in Fair Value Reflected in Earnings		Changes in Fair Value Reflected in AOCI (1), before tax
	(in millions)
Three Months Ended June 30, 2024
Fixed maturity securities	$	0.2	$	(5.0)	$	1.3	$	(2.7)	$	(3.5)	$	(2.7)
Equity securities	4.1		(0.4)		—		(0.3)		3.4		—
Other invested assets	—		—		—		2.3		2.3		—

Total investments	$	4.3	$	(5.4)	$	1.3	$	(0.7)	$	2.2	$	(2.7)

Six Months Ended June 30, 2024
Fixed maturity securities	$	0.3	$	(5.5)	$	0.8	$	(16.4)	$	(4.4)	$	(16.4)
Equity securities	4.2		(0.9)		—		12.7		16.0		—
Other invested assets	—		—		—		2.0		2.0		—

Total investments	$	4.5	$	(6.4)	$	0.8	$	(1.7)	$	13.6	$	(16.4)


Three Months Ended June 30, 2023
Fixed maturity securities	$	0.3	$	(2.0)	$	1.6	$	(19.4)	$	(0.1)	$	(19.4)
Equity securities	—		(2.1)		—		11.8		9.7		—
Other invested assets	—		—		—		1.7		1.7		—

Total investments	$	0.3	$	(4.1)	$	1.6	$	(5.9)	$	11.3	$	(19.4)

Six Months Ended June 30, 2023
Fixed maturity securities	$	0.7	$	(2.6)	$	0.2	$	10.7	$	(1.7)	$	10.7
Equity securities	0.1		(3.4)		—		19.6		16.3		—
Other invested assets	—		—		—		3.1		3.1		—

Total investments	$	0.8	$	(6.0)	$	0.2	$	33.4	$	17.7	$	10.7

(1)AOCI means Accumulated other comprehensive income or loss

Proceeds from sales of fixed maturity securities were $52.7 million and $84.7 million for the three and six months ended June 30, 2024, respectively, compared to $80.7 million and $125.5 million for the three and six months ended June 30, 2023, respectively.

Net investment income was as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Fixed maturity securities	$	23.1	$	23.4	$	45.4	$	47.1
Equity securities	1.7		1.8		3.3		3.6
Other invested assets	1.4		0.9		2.6		1.8
Short-term investments	0.4		0.5		0.9		1.7
Cash equivalents and restricted cash	1.2		0.9		3.5		1.8
Gross investment income	27.8		27.5		55.7		56.0
Investment expenses	(0.9)		(0.7)		(1.9)		(1.6)
Net investment income	$	26.9	$	26.8	$	53.8	$	54.4

The Company is required by various state laws and regulations to support, through securities on deposit or otherwise, its outstanding loss reserves in certain states in which it does business. These laws and regulations govern not only the amount but also the types of securities that are eligible for deposit. As of June 30, 2024 and December 31, 2023, securities having a fair

value of $758.6 million and $748.1 million, respectively, were on deposit. Additionally, standby letters of credit from the FHLB were in place in lieu of $70.0 million of securities on deposit as of both June 30, 2024 and December 31, 2023 (See Note 10).

Certain reinsurance contracts require the Company’s 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 ceding reinsurers at both June 30, 2024 and December 31, 2023 was $3.0 million.

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

6 Months Ended

12 Months Ended

May 23, 2024

Mar. 01, 2024

Feb. 26, 2024

Jun. 30, 2023

Dec. 31, 2023

Jun. 30, 2024

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

Stock-options exercised

23,500

Number of outstanding options or share units

Restricted Stock Units (RSUs) [Member]

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

Share-based compensation award, shares issued

^[1]

17,052

Fair value of awards awarded on grant date

^[1]

$ 0.7

Number of outstanding options or share units

231,821

Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value

^[1]

$ 40.00

Restricted Stock Units (RSUs) [Member] | Officer [Member]

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

Share-based compensation award, shares issued

^[2]

4,712

61,280

Fair value of awards awarded on grant date

^[2]

$ 0.2

$ 2.8

Vesting rights for RSUs awarded

vest 25% on March 15, 2025 and each of the subsequent three anniversaries of that date

Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value

^[2]

$ 45.00

$ 46.36

Performance Shares [Member]

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

Number of outstanding options or share units

202,494

Performance Shares [Member] | Officer [Member]

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

Share-based compensation award, shares issued

^[3]

77,360

Fair value of awards awarded on grant date

^[3]

$ 3.6

Performance share awards performance period

three years

Performance share awards, minimum payout

0.00%

Performance share awards, maximum payout

250.00%

Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value

^[3]

$ 46.36

[1]	All RSUs awarded on this date were awarded to non-employee directors of the Company and vest in full on May 23, 2025.
[2]	These RSUs were awarded to certain employees of the Company on two separate dates and all vest 25% on March 15, 2025 and each of the subsequent three anniversaries of that date.
[3]	These PSUs were awarded to certain employees of the Company and have a performance period of three years. The PSU awards are subject to certain performance goals with payouts that range from 0% to 250% of the target awards. The value shown in the table represents the aggregate number of PSUs awarded at the target level.

Property and Equipment Leases (Details)	Jun. 30, 2024
Minimum [Member]
Lessee, Lease, Description [Line Items]
Lessee, operating lease, remaining lease term	1 year
Lessee, Finance Lease, Term of Contract	1 year
Maximum [Member]
Lessee, Lease, Description [Line Items]
Lessee, operating lease, remaining lease term	5 years
Lessee, operating lease, renewal term	5 years

Segment Reporting Segment Net Income Before Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment Reporting Information [Line Items]
Premiums Written, Gross	$ 207.9	$ 198.4	$ 418.7	$ 393.3
Premiums Written, Net	206.1	196.6	415.2	389.7
Net premiums earned	187.8	177.1	372.6	349.8
Net investment income	26.9	26.8	53.8	54.4
Net Realized and Unrealized (Losses) Gains on Investments	2.2	11.3	13.6	17.7
Other income (loss)	0.1		0.1	(0.2)
Revenues	(217.0)	(215.2)	(440.1)	(421.7)
Losses and loss adjustment expenses	108.8	90.5	225.3	197.9
Commission expense	26.8	23.6	52.3	47.1
Underwriting and general and administrative expenses	41.4	46.0	87.2	90.3
Interest and financing expenses		1.9		4.2
Other Expenses		9.4		9.4
Operating Expenses	177.0	171.4	364.8	348.9
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	40.0	43.8	75.3	72.8
Net income	31.7	34.9	60.0	58.5
Income tax expense	8.3	8.9	15.3	14.3
Insurance Operations
Segment Reporting Information [Line Items]
Premiums Written, Gross	207.9	198.4	418.7	393.3
Premiums Written, Net	206.1	196.6	415.2	389.7
Net premiums earned	187.8	177.1	372.6	349.8
Net investment income	26.9	26.8	53.8	54.4
Net Realized and Unrealized (Losses) Gains on Investments	2.2	11.3	13.6	17.7
Other income (loss)	0.1	0.0	0.1	(0.2)
Revenues	(217.0)	(215.2)	(440.1)	(421.7)
Losses and loss adjustment expenses	108.8	90.5	225.3	197.9
Commission expense	26.8	23.6	52.3	47.1
Underwriting and general and administrative expenses	41.4	46.0	87.2	90.3
Interest and financing expenses	0.0	1.9	0.0	4.2
Other Expenses	0.0	9.4	0.0	9.4
Operating Expenses	177.0	171.4	364.8	348.9
Net (loss) income before income taxes	40.0	43.8	75.3	72.8
Net income	31.7	34.9	60.0	58.5
Income tax expense	$ 8.3	$ 8.9	$ 15.3	$ 14.3

Property and Equipment

6 Months Ended

Jun. 30, 2024

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment Disclosure [Text Block]

Property and Equipment

Property and equipment consists of the following:


	As of June 30,		As of December 31,
	2024		2023
	(in millions)

Furniture and equipment	$	1.8	$	1.8
Leasehold improvements	0.5		0.5
Computers and software	43.3		45.7
Automobiles	0.6		0.6
Property and equipment, gross	46.2		48.6
Accumulated depreciation	(39.5)		(42.1)
Property and equipment, net	$	6.7	$	6.5

Depreciation expenses related to property and equipment for the three and six months ended June 30, 2024 were $0.9 million and $1.9 million, respectively, and $4.8 million for the year ended December 31, 2023. Internally developed software costs that were capitalized were $0.7 million and $1.3 million during the three and six months ended June 30, 2024, respectively, and $1.8 million during the year ended December 31, 2023.

Cloud Computing Arrangements

The Company’s capitalized costs associated with cloud computing arrangements totaled $21.2 million and $28.0 million, which were comprised of service contract fees and implementation costs associated with hosting arrangements as of June 30, 2024 and December 31, 2023, respectively. Total amortization for hosting arrangements was $4.5 million and $7.3 million for the three and six months ended June 30, 2024, respectively, and $16.7 million for the year ended December 31, 2023.

Leases

The Company determines if an arrangement is a lease at the inception of the transaction. Operating leases for offices are presented as both an Operating lease right-of-use (ROU) asset and an Operating lease liability on the Company’s Consolidated Balance Sheets. Finance leases for automobiles are presented as both Property and equipment and Other liabilities on the Company’s Consolidated Balance Sheets.

ROU assets represent the right to use an underlying asset for the lease term and the lease liability represents the obligation to make lease payments arising from the lease transaction. Operating lease assets and liabilities are recognized at the commencement date based on the present value of the lease payments over the lease term. The Company uses collateralized incremental borrowing rates to determine the present value of lease payments. ROU assets also include lease payments less any lease incentives within a lease agreement. The Company’s lease terms may include options to extend or terminate a lease. Lease expense for lease payments is recognized on a straight-line basis over the lease term. As of June 30, 2024, the Company’s operating leases have remaining terms of one year to five years, with options to extend up to five years with no termination provision. The Company’s finance leases have an option to terminate after one year.

Components of lease expense were as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Operating lease expense	$	0.2	$	0.5	$	0.5	$	1.1



Finance lease expense	0.1		—		0.1		0.1
Total lease expense	$	0.3	$	0.5	$	0.6	$	1.2

As of June 30, 2024, the weighted average remaining lease term for operating leases was 3.6 years and for finance leases was 1.6 years. The weighted average discount rate was 1.3% and 7.4% for operating and finance leases, respectively.

Maturities of lease liabilities were as follows:


	As of June 30, 2024
	Operating Leases		Finance Leases
	(in millions)
2024	$	0.9	$	—
2025	1.5		0.1
2026	1.2		—
2027	1.2		—
2028	0.4		—
Thereafter	—		—
Total lease payments	5.2		0.1
Less: imputed interest	(0.1)		—
Total	$	5.1	$	0.1

Supplemental balance sheet information related to leases was as follows:


	As of June 30,		As of December 31,
	2024		2023
	(in millions)
Operating leases:
Operating lease right-of-use asset	$	4.4	$	5.1
Operating lease liability	5.1		5.9
Finance leases:
Property and equipment, gross	0.6		0.6
Accumulated depreciation	(0.5)		(0.4)
Property and equipment, net	0.1		0.2
Other liabilities	$	0.1	$	0.2

Supplemental cash flow information related to leases was as follows:


	Six Months Ended
	June 30,
	2024		2023
	(in millions)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows used for operating leases	$	0.5	$	1.1

Financing cash flows used for finance leases	0.1		0.1

Restructuring, Impairment, and Other Activities Disclosure

Lease Exit and Disposal Costs

During the three months ended June 30, 2023, the Company recorded a non-recurring charge in connection with the early termination of the lease associated with the Company's former corporate headquarters in Reno, Nevada. This charge included a one-time lease termination payment of $7.6 million, a write-off related to remaining leasehold improvements and furniture and equipment of $2.6 million, and estimated miscellaneous expenses associated with exiting the property of $0.2 million. The Company also recognized a lease termination gain pertaining to the elimination of the lease liability, net of an associated ROU asset of $1.0 million, which was included in Other expenses on the Company’s Consolidated Statements of Comprehensive Income (Loss). The decision to terminate this operating lease was undertaken as part of an ongoing review of the Company's facility needs.

Cover Page - shares	6 Months Ended
Cover Page - shares	Jun. 30, 2024	Jul. 30, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2024
Document Transition Report	false
Entity File Number	001-33245
Entity Registrant Name	EMPLOYERS HOLDINGS, INC.
Entity Incorporation, State or Country Code	NV
Entity Tax Identification Number	04-3850065
Entity Address, Address Line One	2340 Corporate Circle, Suite 200
Entity Address, City or Town	Henderson,
Entity Address, State or Province	NV
Entity Address, Postal Zip Code	89074
City Area Code	888
Local Phone Number	682-6671
Title of 12(b) Security	Common Stock, $0.01 par value per share
Trading Symbol	EIG
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		24,836,585
Entity Central Index Key	0001379041
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1

Investments Investments, Held in Trust or on Deposit (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Line of Credit Facility [Line Items]
Other invested assets (cost $86.5 at June 30, 2024 and $82.5 at December 31, 2023)	$ 97.5	$ 91.5
Deposit Assets [Abstract]
Investments	2,376.1	2,278.1
Assets Held-in-trust [Abstract]
Funds Held under Reinsurance Agreements, Asset	3.0	3.0
Federal Home Loan Bank [Member]
Deposit Assets [Abstract]
Line of Credit Facility, Maximum Borrowing Capacity	70.0	70.0
Required by various state laws and regulations to hold securities or letters of credit in depository account [Member]
Deposit Assets [Abstract]
Investments	$ 758.6	$ 748.1

Property and Equipment Leases, Supplement Balance Sheet Information (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets	$ 4.4	$ 5.1
Operating lease liability	5.1	5.9
Property and equipment, gross	46.2	48.6
Accumulated depreciation, depletion and amortization, property and equipment	(39.5)	(42.1)
Property and equipment, net	6.7	6.5
Other liabilities	60.4	58.1
Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, before Accumulated Depreciation and Amortization	0.6	0.6
Finance Lease, Right-of-Use Asset, Accumulated Amortization	0.5	0.4
Finance Lease, Right-of-Use Asset, after Accumulated Amortization	0.1	0.2
Finance lease, liability	$ 0.1	$ 0.2

Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement Parenthetical [Abstract]
OCI, Debt Securities, Available-for-Sale, Gain (Loss), before Adjustment, Tax	$ 1.4	$ 4.1	$ 4.4	$ (1.9)
Other comprehensive income (loss), reclassification adjustment for sale of securities included in net income, tax	$ (0.7)	$ 0.0	$ (0.9)	$ (0.4)

Investments (Tables)

6 Months Ended

Jun. 30, 2024

Investments [Abstract]

Debt Securities, Available-for-sale

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the Company’s available-for-sale (AFS) investments were as follows:


	Amortized Cost		Allowance for Current Expected Credit Losses		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
	(in millions)
At June 30, 2024
Fixed maturity securities
U.S. Treasuries	$	70.4	$	—	$	0.2	$	(3.0)	$	67.6
U.S. Agencies	2.3		—		—		(0.1)		2.2
States and municipalities	189.2		—		1.6		(5.8)		185.0
Corporate securities	1,004.1		(0.7)		4.0		(65.7)		941.7
Residential mortgage-backed securities	424.3		—		0.4		(45.4)		379.3
Commercial mortgage-backed securities	70.4		(0.4)		—		(5.6)		64.4
Asset-backed securities	180.7		(0.2)		0.9		(4.2)		177.2
Collateralized loan obligations	63.6		—		—		(0.1)		63.5
Foreign government securities	12.7		—		—		(2.9)		9.8
Other securities(1)	118.9		(0.6)		0.8		(0.4)		118.7
Total fixed maturity securities	$	2,136.6	$	(1.9)	$	7.9	$	(133.2)	$	2,009.4
Short-term investments	30.9		—		—		—		30.9
Total AFS investments	$	2,167.5	$	(1.9)	$	7.9	$	(133.2)	$	2,040.3


At December 31, 2023
Fixed maturity securities
U.S. Treasuries	$	60.3	$	—	$	0.6	$	(2.5)	$	58.4
U.S. Agencies	2.2		—		—		(0.1)		2.1
States and municipalities	212.3		—		3.1		(5.2)		210.2
Corporate securities	952.8		(2.1)		8.3		(63.2)		895.8
Residential mortgage-backed securities	399.3		—		0.9		(38.0)		362.2
Commercial mortgage-backed securities	70.2		—		—		(6.4)		63.8
Asset-backed securities	131.8		—		1.0		(4.8)		128.0
Collateralized loan obligations	92.2		—		—		(0.7)		91.5
Foreign government securities	12.7		—		—		(2.3)		10.4
Other securities(1)	114.2		(0.6)		1.0		(0.7)		113.9
Total fixed maturity securities	$	2,048.0	$	(2.7)	$	14.9	$	(123.9)	$	1,936.3
Short-term investments	33.1		—		—		—		33.1
Total AFS investments	$	2,081.1	$	(2.7)	$	14.9	$	(123.9)	$	1,969.4

(1)Other securities within fixed maturity securities consist of bank loans, which are classified as AFS and reported at fair value.

Equity securities table

The cost and estimated fair value of the Company’s equity securities recorded at fair value at June 30, 2024 and December 31, 2023 were as follows:


	Cost		Estimated Fair Value
	(in millions)
At June 30, 2024
Equity securities at fair value
Industrial and miscellaneous	$	111.5	$	202.5
Other	22.9		30.1
Total equity securities at fair value	$	134.4	$	232.6




At December 31, 2023
Equity securities at fair value
Industrial and miscellaneous	$	104.4	$	181.7
Other	21.5		29.5
Total equity securities at fair value	$	125.9	$	211.2

Other invested assets

Investments classified by contractual maturity date table


	Amortized Cost		Estimated Fair Value
	(in millions)
Due in one year or less	$	46.3	$	45.6
Due after one year through five years	644.6		622.5
Due after five years through ten years	613.0		571.7
Due after ten years	93.7		85.2
Mortgage and asset-backed securities	739.0		684.4
Total	$	2,136.6	$	2,009.4

Unrealized loss on investments table


	June 30, 2024					December 31, 2023
	Estimated Fair Value		Gross Unrealized Losses		Number of Issues	Estimated Fair Value		Gross Unrealized Losses		Number of Issues
	(dollars in millions)
Less than 12 months:
Fixed maturity securities
U.S. Treasuries	$	20.1	$	(0.1)	7	$	11.9	$	(0.1)	5

States and municipalities	33.0		(0.5)		13	39.5		(0.3)		15
Corporate securities	134.6		(1.4)		36	26.1		(0.8)		13
Residential mortgage-backed securities	42.4		(0.3)		25	15.8		(0.2)		15

Asset-backed securities	66.3		(0.4)		22	24.0		(0.1)		15
Collateralized loan obligations	—		—		—	—		—		—

Other securities	23.3		(0.3)		117	12.6		(0.1)		70
Total fixed maturity securities	319.7		(3.0)		220	129.9		(1.6)		133

Total less than 12 months	$	319.7	$	(3.0)	220	$	129.9	$	(1.6)	133

12 months or greater:
Fixed maturity securities
U.S. Treasuries	$	34.8	$	(2.9)	11	$	23.7	$	(2.4)	7
U.S. Agencies	2.2		(0.1)		1	2.2		(0.1)		1
States and municipalities	83.6		(5.3)		36	73.5		(4.9)		32
Corporate securities	666.7		(64.3)		282	684.5		(62.4)		331
Residential mortgage-backed securities	293.6		(45.1)		234	306.6		(37.8)		228
Commercial mortgage-backed securities	52.5		(5.6)		23	53.0		(6.4)		24
Asset-backed securities	48.6		(3.8)		36	47.0		(4.7)		29
Collateralized loan obligations	5.4		(0.1)		3	80.5		(0.7)		21
Foreign government securities	9.8		(2.9)		2	10.4		(2.3)		2
Other securities	3.0		(0.1)		22	10.2		(0.6)		58
Total fixed maturity securities	1,200.2		(130.2)		650	1,291.6		(122.3)		733
Total 12 months or greater	$	1,200.2	$	(130.2)	650	$	1,291.6	$	(122.3)	733

Unrealized gain (loss) on investments


	Gross Realized Gains		Gross Realized Losses		Net Decrease in CECL Allowance		Change in Net Unrealized Gains (Losses)		Changes in Fair Value Reflected in Earnings		Changes in Fair Value Reflected in AOCI (1), before tax
	(in millions)
Three Months Ended June 30, 2024
Fixed maturity securities	$	0.2	$	(5.0)	$	1.3	$	(2.7)	$	(3.5)	$	(2.7)
Equity securities	4.1		(0.4)		—		(0.3)		3.4		—
Other invested assets	—		—		—		2.3		2.3		—

Total investments	$	4.3	$	(5.4)	$	1.3	$	(0.7)	$	2.2	$	(2.7)

Six Months Ended June 30, 2024
Fixed maturity securities	$	0.3	$	(5.5)	$	0.8	$	(16.4)	$	(4.4)	$	(16.4)
Equity securities	4.2		(0.9)		—		12.7		16.0		—
Other invested assets	—		—		—		2.0		2.0		—

Total investments	$	4.5	$	(6.4)	$	0.8	$	(1.7)	$	13.6	$	(16.4)


Three Months Ended June 30, 2023
Fixed maturity securities	$	0.3	$	(2.0)	$	1.6	$	(19.4)	$	(0.1)	$	(19.4)
Equity securities	—		(2.1)		—		11.8		9.7		—
Other invested assets	—		—		—		1.7		1.7		—

Total investments	$	0.3	$	(4.1)	$	1.6	$	(5.9)	$	11.3	$	(19.4)

Six Months Ended June 30, 2023
Fixed maturity securities	$	0.7	$	(2.6)	$	0.2	$	10.7	$	(1.7)	$	10.7
Equity securities	0.1		(3.4)		—		19.6		16.3		—
Other invested assets	—		—		—		3.1		3.1		—

Total investments	$	0.8	$	(6.0)	$	0.2	$	33.4	$	17.7	$	10.7

Investment income table

Net investment income was as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Fixed maturity securities	$	23.1	$	23.4	$	45.4	$	47.1
Equity securities	1.7		1.8		3.3		3.6
Other invested assets	1.4		0.9		2.6		1.8
Short-term investments	0.4		0.5		0.9		1.7
Cash equivalents and restricted cash	1.2		0.9		3.5		1.8
Gross investment income	27.8		27.5		55.7		56.0
Investment expenses	(0.9)		(0.7)		(1.9)		(1.6)
Net investment income	$	26.9	$	26.8	$	53.8	$	54.4

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Accumulated Other Comprehensive Income

6 Months Ended

Jun. 30, 2024

Accumulated Other Comprehensive Income [Abstract]

Accumulated Other Comprehensive Income, Net

Accumulated Other Comprehensive Loss

Accumulated other comprehensive loss is comprised of unrealized gains and losses on investments classified as AFS, net of deferred taxes. The following table summarizes the components of accumulated other comprehensive loss:


	June 30, 2024		December 31, 2023
	(in millions)
Net unrealized losses on AFS investments, before taxes	$	(125.3)	$	(108.9)
Deferred tax benefit on net unrealized losses	26.3		22.9
Total accumulated other comprehensive loss	$	(99.0)	$	(86.0)

Accumulated Other Comprehensive Income (Tables)

6 Months Ended

Jun. 30, 2024

Accumulated Other Comprehensive Income [Abstract]

Schedule of accumulated other comprehensive income (loss) table

The following table summarizes the components of accumulated other comprehensive loss:


	June 30, 2024		December 31, 2023
	(in millions)
Net unrealized losses on AFS investments, before taxes	$	(125.3)	$	(108.9)
Deferred tax benefit on net unrealized losses	26.3		22.9
Total accumulated other comprehensive loss	$	(99.0)	$	(86.0)

Current Expected Credit Losses (Tables)

6 Months Ended

Jun. 30, 2024

Credit Loss [Abstract]

Premium Receivable, Allowance for Credit Loss [Table Text Block]

The table below shows the changes in CECL on premiums receivable.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Beginning balance of CECL on premiums receivable	$	19.7	$	14.0	$	17.9	$	12.8
Net change in CECL provision	4.3		3.9		10.1		7.2
Write-offs charged against CECL	(3.1)		(0.5)		(5.0)		(1.2)
Recoveries collected	(2.1)		(2.2)		(4.2)		(3.6)
Ending balance of CECL on premiums receivable	$	18.8	$	15.2	$	18.8	$	15.2

Reinsurance Recoverable, Allowance for Credit Loss [Table Text Block]

The table below shows the changes in CECL on reinsurance recoverables.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Beginning balance of CECL on reinsurance recoverables	$	0.9	$	0.9	$	0.9	$	0.9
Net change in CECL provision	—		—		—		—


Ending balance of CECL on reinsurance recoverables	$	0.9	$	0.9	$	0.9	$	0.9

Debt Securities, Available-for-sale, Allowance for Credit Loss [Table Text Block]

The table below shows the changes in the allowance for CECL on AFS investments.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Beginning balance of CECL on AFS investments	$	3.2	$	5.9	$	2.7	$	4.5
Net change in CECL provision	0.5		(1.1)		1.1		0.5
Reductions in allowance from disposals	(1.8)		(0.5)		(1.9)		(0.7)
Write-offs charged against the allowance	—		—		—		—
Recoveries of amounts previously written off	—		—		—		—
Ending balance of CECL on AFS investments	$	1.9	$	4.3	$	1.9	$	4.3

Valuation of Financial Instruments Investments at NAV (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Investments at NAV [Abstract]
Fair value investments entities that calculate net asset value per share liquidating investment original expected lives increments	1 year
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	$ 18.3
Cash Equivalents Measured at Net Asset Value	89.3	$ 197.2
Other invested assets at NAV	$ 97.5	$ 91.5
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value investments entities that calculate net asset value per share liquidating investment original expected lives increments	1 year
Maximum [Member]
Investments at NAV [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period	12 years
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period	12 years
Minimum [Member]
Investments at NAV [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period	3 years
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Liquidating Investment, Remaining Period	3 years

- Definition

+ References

+ Details

Investments Available for Sale Securities (Details) - USD ($) $ in Millions	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	$ 2,136.6		$ 2,048.0
Debt securities, available-for-sale, gross unrealized gain	7.9		14.9
Debt securities, available-for-sale, gross unrealized loss	(133.2)		(123.9)
Fixed maturity securities, fair value	2,009.4		1,936.3
Total AFS, amortized cost	2,167.5		2,081.1
Total AFS, gross unrealized gain	7.9		14.9
Total AFS, gross unrealized loss	(133.2)		(123.9)
Short-term investments at fair value (amortized cost $30.9 at June 30, 2024 and $33.1 at December 31, 2023)	30.9		33.1
Total AFS investments	2,040.3		1,969.4
Debt Securities, Available-for-sale, Allowance for Credit Loss	(1.9)	$ (3.2)	(2.7)	$ (4.3)	$ (5.9)	$ (4.5)
US Treasury Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	70.4		60.3
Debt securities, available-for-sale, gross unrealized gain	0.2		0.6
Debt securities, available-for-sale, gross unrealized loss	(3.0)		(2.5)
Fixed maturity securities, fair value	67.6		58.4
Debt Securities, Available-for-sale, Allowance for Credit Loss	0.0		0.0
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	2.3		2.2
Debt securities, available-for-sale, gross unrealized gain	0.0		0.0
Debt securities, available-for-sale, gross unrealized loss	(0.1)		(0.1)
Fixed maturity securities, fair value	2.2		2.1
Debt Securities, Available-for-sale, Allowance for Credit Loss	0.0		0.0
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	189.2		212.3
Debt securities, available-for-sale, gross unrealized gain	1.6		3.1
Debt securities, available-for-sale, gross unrealized loss	(5.8)		(5.2)
Fixed maturity securities, fair value	185.0		210.2
Debt Securities, Available-for-sale, Allowance for Credit Loss	0.0		0.0
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	1,004.1		952.8
Debt securities, available-for-sale, gross unrealized gain	4.0		8.3
Debt securities, available-for-sale, gross unrealized loss	(65.7)		(63.2)
Fixed maturity securities, fair value	941.7		895.8
Debt Securities, Available-for-sale, Allowance for Credit Loss	(0.7)		(2.1)
Residential Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	424.3		399.3
Debt securities, available-for-sale, gross unrealized gain	0.4		0.9
Debt securities, available-for-sale, gross unrealized loss	(45.4)		(38.0)
Fixed maturity securities, fair value	379.3		362.2
Debt Securities, Available-for-sale, Allowance for Credit Loss	0.0		0.0
Commercial Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	70.4		70.2
Debt securities, available-for-sale, gross unrealized gain	0.0		0.0
Debt securities, available-for-sale, gross unrealized loss	(5.6)		(6.4)
Fixed maturity securities, fair value	64.4		63.8
Debt Securities, Available-for-sale, Allowance for Credit Loss	(0.4)		0.0
Asset-backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	180.7		131.8
Debt securities, available-for-sale, gross unrealized gain	0.9		1.0
Debt securities, available-for-sale, gross unrealized loss	(4.2)		(4.8)
Fixed maturity securities, fair value	177.2		128.0
Debt Securities, Available-for-sale, Allowance for Credit Loss	0.2		0.0
Foreign Government Debt
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	12.7		12.7
Debt securities, available-for-sale, gross unrealized gain	0.0		0.0
Debt securities, available-for-sale, gross unrealized loss	(2.9)		(2.3)
Fixed maturity securities, fair value	9.8		10.4
Debt Securities, Available-for-sale, Allowance for Credit Loss	0.0		0.0
Collateralized Loan Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	63.6		92.2
Debt securities, available-for-sale, gross unrealized gain	0.0		0.0
Debt securities, available-for-sale, gross unrealized loss	(0.1)		(0.7)
Fixed maturity securities, fair value	63.5		91.5
Debt Securities, Available-for-sale, Allowance for Credit Loss	0.0		0.0
Other Debt Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, amortized cost	118.9		114.2
Debt securities, available-for-sale, gross unrealized gain	0.8		1.0
Debt securities, available-for-sale, gross unrealized loss	(0.4)		(0.7)
Fixed maturity securities, fair value	118.7		113.9
Debt Securities, Available-for-sale, Allowance for Credit Loss	(0.6)		(0.6)
Short-term Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Total AFS, amortized cost	30.9		33.1
Total AFS, gross unrealized gain	0.0		0.0
Total AFS, gross unrealized loss	0.0		0.0
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0.0		$ 0.0

Earnings Per Share (Tables)

6 Months Ended

Jun. 30, 2024

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 number of shares outstanding used in the earnings per common share calculations.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions, except share data)
Net income	$	31.7	$	34.9	$	60.0	$	58.5
Weighted average number of shares outstanding—basic	25,278,473		26,691,652		25,312,208		26,932,897
Effect of dilutive securities:
PSUs	47,684		85,691		81,353		113,469
Stock options	—		—		—		4,143
RSUs	37,784		25,997		56,396		46,160
Potential dilutive shares	85,468		111,688		137,749		163,772
Weighted average number of shares outstanding—diluted	25,363,941		26,803,340		25,449,957		27,096,669

Diluted earnings per share excludes outstanding potential dilutive shares in periods where the inclusion of such securities would be anti-dilutive under the treasury stock methodology. Potential dilutive shares of 82,072 and 77,252 for the three months ended June 30, 2024 and 2023, respectively, and potential dilutive shares of 41,036 and 38,626 for the six months ended June 30, 2024 and 2023, respectively, were excluded from the Company's diluted earnings per share computations because they were anti-dilutive.

Liability for Unpaid Losses and Loss Adjustment Expenses

3 Months Ended

Jun. 30, 2024

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.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Unpaid losses and LAE at beginning of period	$	1,874.5	$	1,953.7	$	1,884.5	$	1,960.7
Less reinsurance recoverable, excluding CECL allowance, on unpaid losses and LAE	424.0		440.3		428.4		445.4
Net unpaid losses and LAE at beginning of period	1,450.5		1,513.4		1,456.1		1,515.3
Losses and LAE, net of reinsurance, incurred during the period related to:
Current period	120.0		112.2		238.7		221.8
Prior periods	(9.1)		(19.7)		(9.2)		(19.9)
Total net losses and LAE incurred during the period	110.9		92.5		229.5		201.9
Paid losses and LAE, net of reinsurance, related to:
Current period	24.1		26.5		30.9		32.1
Prior periods	104.7		88.4		222.1		194.1
Total net paid losses and LAE during the period	128.8		114.9		253.0		226.2
Ending unpaid losses and LAE, net of reinsurance	1,432.6		1,491.0		1,432.6		1,491.0
Reinsurance recoverable, excluding CECL allowance, on unpaid losses and LAE	418.3		436.2		418.3		436.2
Unpaid losses and LAE at end of period	$	1,850.9	$	1,927.2	$	1,850.9	$	1,927.2

Total net losses and LAE included in the above table exclude amortization of the deferred reinsurance gain—LPT Agreement and LPT Contingent Commission Adjustments, which totaled $2.1 million and $2.0 million for the three months ended June 30, 2024 and 2023, respectively, and $4.2 million and $4.0 million for the six months ended June 30, 2024 and 2023, respectively (see Note 9).

The change in incurred losses and LAE attributable to prior periods for the three months ended June 30, 2024, included $9.3 million of net favorable loss reserve development on the Company's voluntary risk business, partially offset by $0.2 million of net unfavorable loss reserve development on the Company's assigned risk business. The change in incurred losses and LAE attributable to prior periods for the six months ended June 30, 2024, included $9.3 million of net favorable loss reserve development on the Company's voluntary risk business, partially offset by $0.1 million of net unfavorable loss reserve development on the Company's assigned risk business.

The favorable prior year loss reserve development on the Company's voluntary business during the three and six months ended June 30, 2024 resulted from continued overall favorable loss experience, which related primarily to accident years 2022 and prior, partially offset by unfavorable prior year loss experience in accident year 2023 associated with certain large claims.

The change in incurred losses and LAE attributable to prior periods for the three months ended June 30, 2023, included $20.0 million of net favorable loss reserve development on the Company's voluntary risk business, partially offset by $0.3 million of net unfavorable loss reserve development on the Company's assigned risk business. The change in incurred losses and LAE attributable to prior periods for the six months ended June 30, 2023, included $20.0 million of net favorable loss reserve development on the Company's voluntary risk business, partially offset by $0.1 million of net unfavorable loss reserve development on the Company's assigned risk business.

The favorable prior year loss reserve development on the Company's voluntary business during the three and six months ended June 30, 2023 resulted from continued overall favorable loss experience, which related primarily to accident years 2020 and prior.

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Income tax expense	$ 8.3	$ 8.9	$ 15.3	$ 14.3
Effective tax rate	20.80%	20.30%	20.30%	19.60%
Share Repurchase Program, Excise Tax			$ 0.2		$ 0.7

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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+ Details

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Millions	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Pay vs Performance Disclosure
Net income	$ 31.7	$ 34.9	$ 60.0	$ 58.5

- Definition

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

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-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 60B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482689/260-10-45-60B

Reference 33: http://www.xbrl.org/2003/role/disclosureRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-7

Reference 34: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 35: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-1A

Reference 36: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-1B

Reference 37: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

Investments Investments, Net Realized Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Realized Investment Gains (Losses)
Total gross realized gains	$ 4.3	$ 0.3	$ 4.5	$ 0.8
Investments, Gross Realized Losses	(5.4)	(4.1)	(6.4)	(6.0)
Allowance for Credit Loss
Investments, Net (Increase)/Decrease in CECL Allowance	1.3	1.6	0.8	0.2
Debt and Equity Securities, Unrealized Gain (Loss)
Change in net unrealized gains (losses)	(0.7)	(5.9)	(1.7)	33.4
Net Realized and Unrealized (Losses) Gains on Investments	2.2	11.3	13.6	17.7
AFS, Change in Unrealized Gains (Losses) on Fixed Maturity and Equity Securities reflected in AOCI	(2.7)	(19.4)	(16.4)	10.7
Proceeds from Sale and Maturity of Debt Securities, Available-for-Sale
Proceeds from sale of fixed maturity securities	52.7	80.7	84.7	125.5
Debt Securities [Member]
Realized Investment Gains (Losses)
Debt Securities, Available-for-sale, Realized Gain	0.2	0.3	0.3	0.7
Debt Securities, Available-for-sale, Realized Loss	(5.0)	(2.0)	(5.5)	(2.6)
Allowance for Credit Loss
Investments, Net (Increase)/Decrease in CECL Allowance	1.3	1.6	0.8	0.2
Debt and Equity Securities, Unrealized Gain (Loss)
Change in net unrealized gains (losses)	(2.7)	(19.4)	(16.4)	10.7
Net Realized and Unrealized (Losses) Gains on Investments	(3.5)	(0.1)	(4.4)	(1.7)
AFS, Change in Unrealized Gains (Losses) on Fixed Maturity and Equity Securities reflected in AOCI	(2.7)	(19.4)	(16.4)	10.7
Equity Securities [Member]
Realized Investment Gains (Losses)
Equity Securities, FV-NI, Realized Gain	4.1	0.0	4.2	0.1
Equity Securities, FV-NI, Realized Loss	(0.4)	(2.1)	(0.9)	(3.4)
Allowance for Credit Loss
Investments, Net (Increase)/Decrease in CECL Allowance	0.0	0.0	0.0	0.0
Debt and Equity Securities, Unrealized Gain (Loss)
Change in net unrealized gains (losses)	(0.3)	11.8	12.7	19.6
Net Realized and Unrealized (Losses) Gains on Investments	3.4	9.7	16.0	16.3
AFS, Change in Unrealized Gains (Losses) on Fixed Maturity and Equity Securities reflected in AOCI	0.0	0.0	0.0	0.0
Other Investments [Member]
Realized Investment Gains (Losses)
Gain on Sale of Investments	0.0	0.0	0.0	0.0
Loss on Sale of Investments	0.0	0.0	0.0	0.0
Allowance for Credit Loss
Investments, Net (Increase)/Decrease in CECL Allowance	0.0	0.0	0.0	0.0
Debt and Equity Securities, Unrealized Gain (Loss)
Change in net unrealized gains (losses)	2.3	1.7	2.0	3.1
Net Realized and Unrealized (Losses) Gains on Investments	2.3	1.7	2.0	3.1
AFS, Change in Unrealized Gains (Losses) on Fixed Maturity and Equity Securities reflected in AOCI	$ 0.0	$ 0.0	$ 0.0	$ 0.0

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Jun. 30, 2024
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	Item 5. Other Information Rule 10b5-1 Trading Plans During the three months ended June 30, 2024, no director or officer of the Company adopted or terminated a "Rule 10b5-1 trading arrangement" or "non-Rule 10b5-1 trading arrangement," as each such term is defined in Item 408(a) of Regulation S-K.
Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false

Liability for Unpaid Losses and Loss Adjustment Expenses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Unpaid losses and LAE at beginning of period	$ 1,874.5	$ 1,953.7	$ 1,884.5	$ 1,960.7
Less reinsurance recoverable, excluding CECL allowance, on unpaid losses and LAE	424.0	440.3	428.4	445.4
Net unpaid losses and LAE at beginning of period	1,450.5	1,513.4	1,456.1	1,515.3
Losses and LAE, net of reinsurance, incurred during the period related to:
Current period	120.0	112.2	238.7	221.8
Prior periods	(9.1)	(19.7)	(9.2)	(19.9)
Total net losses and LAE incurred during the period	110.9	92.5	229.5	201.9
Deduct payments for losses and LAE, net of reinsurance, related to:
Current period	24.1	26.5	30.9	32.1
Prior periods	104.7	88.4	222.1	194.1
Total net paid losses and LAE during the period	128.8	114.9	253.0	226.2
Ending unpaid losses and LAE, net of reinsurance	1,432.6	1,491.0	1,432.6	1,491.0
Reinsurance recoverable, excluding CECL allowance, on unpaid losses and LAE	418.3	436.2	418.3	436.2
Unpaid losses and LAE at end of period	1,850.9	1,927.2	1,850.9	1,927.2
Impact of the LPT Agreement	2.1	2.0	4.2	4.0
Involuntary Assigned Risk Business [Member]
Losses and LAE, net of reinsurance, incurred during the period related to:
Prior periods	0.2	0.3	0.1	0.1
Voluntary Risk Business [Member]
Losses and LAE, net of reinsurance, incurred during the period related to:
Prior periods	$ (9.3)	$ (20.0)	$ (9.3)	$ (20.0)

Fair Value Measures and Disclosures on recurring basis, unobservable inputs (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	$ 13.6	$ 1.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	(0.5)	0.2
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 59.3	$ 25.4	$ 46.2	$ 24.2

Current Expected Credit Losses

6 Months Ended

Jun. 30, 2024

Credit Loss [Abstract]

Credit Losses

Current Expected Credit Losses

Premiums Receivable

Premiums receivable balances are all due within one year. The Company currently determines the allowance for premiums receivable based on an internal aging schedule using collectability and historical payment patterns, as well as current and expected future market conditions to determine the appropriateness of the allowance. Historical payment patterns and future market conditions provide the basis for the estimation along with similar risk characteristics and the Company's business strategy, which have not changed significantly over time. Changes in the allowance for CECL are recorded through underwriting and general and administrative expenses.

The table below shows the changes in CECL on premiums receivable.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Beginning balance of CECL on premiums receivable	$	19.7	$	14.0	$	17.9	$	12.8
Net change in CECL provision	4.3		3.9		10.1		7.2
Write-offs charged against CECL	(3.1)		(0.5)		(5.0)		(1.2)
Recoveries collected	(2.1)		(2.2)		(4.2)		(3.6)
Ending balance of CECL on premiums receivable	$	18.8	$	15.2	$	18.8	$	15.2

Reinsurance Recoverable

In assessing an allowance for reinsurance assets, which includes reinsurance recoverables and contingent commission receivables, the Company considers historical information, financial strength of reinsurers, collateralization amounts, and ratings to determine the appropriateness of the allowance. Historically, the Company has not experienced a credit loss from reinsurance transactions. In assessing future default, the Company evaluated the CECL allowance under the ratings-based method using the A.M. Best's Average Cumulative Net Impairment Rates. Reinsurer ratings are also assessed through this process. Changes in the allowance for CECL are recorded through underwriting and general and administrative expenses.

The table below shows the changes in CECL on reinsurance recoverables.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Beginning balance of CECL on reinsurance recoverables	$	0.9	$	0.9	$	0.9	$	0.9
Net change in CECL provision	—		—		—		—


Ending balance of CECL on reinsurance recoverables	$	0.9	$	0.9	$	0.9	$	0.9

Investments

The Company assesses all AFS investments in an unrealized loss position for CECL. The Company first assesses whether it intends to sell, or it is more likely than not that it will be required to sell, the security before recovery of its amortized cost basis. If either of the criteria is met, the security's amortized cost basis is written down to its fair value. For AFS investments that do not meet either criteria, the Company evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. Any impairment that has not been recorded through an allowance for credit losses is recognized in Accumulated other

comprehensive loss on the Company's Consolidated Balance Sheets. Changes in the allowance for CECL are recorded as a Realized gain or loss on investments on the Company’s Consolidated Statements of Comprehensive Income (Loss).

As of June 30, 2024, the Company established an aggregate allowance for CECL in the amount of $1.9 million. For the Company’s investments in fixed maturity debt securities, the allowance for CECL was determined by: (i) observing the credit characteristics of those debt securities that may have demonstrated a credit loss as of that date and by comparing the present value of cash flows expected to be collected to its amortized cost basis; and (ii) observing the credit characteristics of those debt securities that are expected to demonstrate a credit loss in the future by comparing the present value of cash flows expected to be collected to its amortized cost basis. The expected present value of cash flows are calculated using scenario based credit loss models derived from the discounted cash flows under the Comprehensive Capital Analysis Review framework, which is adopted by the Federal Reserve.

As of June 30, 2024, the Company did not intend to sell any of its AFS investments in which its amortized cost exceeded its fair value.

Accrued interest receivable on AFS investments totaled $16.7 million at June 30, 2024 and is excluded from the estimate of credit losses based on historically timely payments.

The table below shows the changes in the allowance for CECL on AFS investments.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Beginning balance of CECL on AFS investments	$	3.2	$	5.9	$	2.7	$	4.5
Net change in CECL provision	0.5		(1.1)		1.1		0.5
Reductions in allowance from disposals	(1.8)		(0.5)		(1.9)		(0.7)
Write-offs charged against the allowance	—		—		—		—
Recoveries of amounts previously written off	—		—		—		—
Ending balance of CECL on AFS investments	$	1.9	$	4.3	$	1.9	$	4.3

- Definition

The entire disclosure for credit loss on financial instrument measured at amortized cost basis, net investment in lease, off-balance sheet credit exposure, and available-for-sale debt security.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 44
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-44

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-21

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-4

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-11

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-7

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-8

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 20
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-20

+ Details

Fair Value of Financial Instruments, Fair Value Inputs (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	$ 2,009.4	$ 1,936.3
Equity securities at fair value (cost $134.4 at June 30, 2024 and $125.9 at December 31, 2023)	232.6	211.2
Equity Securities, FV-NI	232.6	211.2
Short-term investments at fair value (amortized cost $30.9 at June 30, 2024 and $33.1 at December 31, 2023)	30.9	33.1
Investments	2,376.1	2,278.1
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	232.6	211.2
Short-term investments at fair value (amortized cost $30.9 at June 30, 2024 and $33.1 at December 31, 2023)	9.1	17.6
Investments	241.7	228.8
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	0.0	0.0
Short-term investments at fair value (amortized cost $30.9 at June 30, 2024 and $33.1 at December 31, 2023)	21.8	15.5
Investments	1,971.9	1,905.6
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	0.0	0.0
Short-term investments at fair value (amortized cost $30.9 at June 30, 2024 and $33.1 at December 31, 2023)	0.0	0.0
Investments	59.3	46.2
Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	1,950.1	1,890.1
Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	59.3	46.2
US Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	67.6	58.4
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	67.6	58.4
US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
US Government Agencies Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	2.2	2.1
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	2.2	2.1
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	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]
Fixed maturity securities, fair value	185.0	210.2
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	185.0	210.2
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	941.7	895.8
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	896.4	863.7
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	45.3	32.1
Residential Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	379.3	362.2
Residential Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Residential Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	379.3	362.2
Residential Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Commercial Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	64.4	63.8
Commercial Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Commercial Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	64.4	63.8
Commercial Mortgage Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Asset-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	177.2	128.0
Asset-backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Asset-backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	163.2	113.9
Asset-backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	14.0	14.1
Foreign Government Debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	9.8	10.4
Foreign Government Debt \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Foreign Government Debt \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	9.8	10.4
Foreign Government Debt \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Collateralized Loan Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	63.5	91.5
Collateralized Loan Obligations [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Collateralized Loan Obligations [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	63.5	91.5
Collateralized Loan Obligations [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Other Debt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	118.7	113.9
Other Debt Obligations [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Other Debt Obligations [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	118.7	113.9
Other Debt Obligations [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities, fair value	0.0	0.0
Industrial and Miscellaneous [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	202.5	181.7
Industrial and Miscellaneous [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	202.5	181.7
Industrial and Miscellaneous [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	0.0	0.0
Industrial and Miscellaneous [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities at fair value (cost $134.4 at June 30, 2024 and $125.9 at December 31, 2023)		0.0
Equity Securities, FV-NI	0.0
Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	30.1	29.5
Other [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	30.1	29.5
Other [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	0.0	0.0
Other [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	$ 0.0	$ 0.0

Fair Value of Financial Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investments at fair value	$ 2,272.9	$ 2,180.6
Total Investments at fair value, estimated fair value	2,272.9	2,180.6
Cash and cash equivalents	95.5	226.4
Cash and cash equivalents, estimated fair value	95.5	226.4
Restricted cash and cash equivalents	0.2	0.2
Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restricted cash and cash equivalents	$ 0.2	$ 0.2

Current Expected Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Current Expected Credit Losses [Abstract]
Premium Receivable, Allowance for Credit Loss	$ 18.8	$ 15.2	$ 18.8	$ 15.2	$ 19.7	$ 17.9	$ 14.0	$ 12.8
Premium Receivable, Allowance for Credit Loss, Period Increase (Decrease)	4.3	3.9	10.1	7.2
Premium Receivable, Allowance for Credit Loss, Writeoff	(3.1)	(0.5)	(5.0)	(1.2)
Premium Receivable, Allowance for Credit Loss, Recovery	(2.1)	(2.2)	(4.2)	(3.6)
Reinsurance recoverables on unpaid losses, allowance	0.9	0.9	0.9	0.9	0.9	0.9	0.9	0.9
Reinsurance Recoverable, Allowance for Credit Loss, Period Increase (Decrease)	0.0	0.0	0.0	0.0
Accrued investment income	16.7		16.7			16.3
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	1.9	4.3	1.9	4.3	$ 3.2	$ 2.7	$ 5.9	$ 4.5
Debt Securities, Available-for-sale, Allowance for Credit Loss, Period Increase (Decrease)	0.5	(1.1)	1.1	0.5
Debt Securities, Available-for-sale, Allowance for Credit Loss, Securities Sold	(1.8)	(0.5)	(1.9)	(0.7)
Debt Securities, Available-for-sale, Allowance for Credit Loss, Recovery	$ 0.0	$ 0.0	$ 0.0	$ 0.0

Consolidated Balance Sheets Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Available for sale:
Debt securities, available-for-sale, amortized cost	$ 2,136.6	$ 2,048.0
Debt Securities, Available-for-sale, Allowance for Credit Loss	1.9	2.7
Equity Securities, FV-NI, Cost	134.4	125.9
Other Investments and Securities, at Cost	86.5	82.5
Available for sale, short-term investments, at amortized cost	30.9	33.1
Accounts Receivable, Allowance for Credit Loss, Current	18.8	17.9
Reinsurance recoverables on unpaid losses, allowance	$ 0.9	$ 0.9
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)	58,167,193	58,055,968
Common stock, shares outstanding (in shares)	24,896,116	25,369,753
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)	33,271,077	32,686,215

Consolidated Statements of Stockholders Equity Statement - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income, Net	Treasury Stock, Common
Stockholders' equity, shares at Dec. 31, 2022		57,876,287
Stockholders' equity, value at Dec. 31, 2022	$ 944.2	$ 0.6	$ 414.6	$ 1,295.6	$ (138.9)	$ (627.7)
Stock-based obligations, shares		0
Stock-based obligations, value	$ 3.2	$ 0.0	3.2	0.0	0.0	0.0
Stock-options exercised, shares	23,500	23,500
Stock-options exercised, value	$ 0.7	$ 0.0	0.7	0.0	0.0	0.0
Vesting of RSUs and PSUs, net of shares withheld to satisfy minimum tax withholding, shares		97,698
Vesting of RSUs and PSUs, net of shares withheld to satisfy minimum tax withholding, value	(1.4)	$ 0.0	(1.4)	0.0	0.0	0.0
Acquisition of common stock, shares		0
Acquisition of common stock, value	(47.2)	$ 0.0	0.0	0.0	0.0	(47.2)
Dividends declared, shares		0
Dividends declared, value	(14.7)	$ 0.0	0.0	(14.7)	0.0	0.0
Net income	58.5	0.0	0.0	58.5	0.0	0.0
Change in net unrealized gains in investments, net of tax	8.4	$ 0.0	0.0	0.0	8.4	0.0
Stockholders' equity, shares at Jun. 30, 2023		57,997,485
Stockholders' equity, value at Jun. 30, 2023	951.7	$ 0.6	417.1	1,339.4	(130.5)	(674.9)
Other comprehensive income (loss), unrealized holding gain (loss) on securities arising during period, tax	(2.3)
Stockholders' equity, shares at Dec. 31, 2022		57,876,287
Stockholders' equity, value at Dec. 31, 2022	$ 944.2	$ 0.6	414.6	1,295.6	(138.9)	(627.7)
Stock-options exercised, shares	23,500
Stockholders' equity, shares at Dec. 31, 2023	58,055,968	58,055,968
Stockholders' equity, value at Dec. 31, 2023	$ 1,013.9	$ 0.6	419.8	1,384.3	(86.0)	(704.8)
Stockholders' equity, shares at Mar. 31, 2023		57,985,389
Stockholders' equity, value at Mar. 31, 2023	974.1	$ 0.6	415.6	1,312.1	(115.1)	(639.1)
Stock-based obligations, shares		0
Stock-based obligations, value	1.5	$ 0.0	1.5	0.0	0.0	0.0
Vesting of RSUs and PSUs, net of shares withheld to satisfy minimum tax withholding, shares		12,096
Vesting of RSUs and PSUs, net of shares withheld to satisfy minimum tax withholding, value	0.0	$ 0.0	0.0	0.0	0.0	0.0
Acquisition of common stock, shares		0
Acquisition of common stock, value	(35.8)	$ 0.0	0.0	0.0	0.0	(35.8)
Dividends declared, shares		0
Dividends declared, value	(7.6)	$ 0.0	0.0	(7.6)	0.0	0.0
Net income	34.9	0.0	0.0	34.9	0.0	0.0
Change in net unrealized gains in investments, net of tax	(15.4)	$ 0.0	0.0	0.0	(15.4)	0.0
Stockholders' equity, shares at Jun. 30, 2023		57,997,485
Stockholders' equity, value at Jun. 30, 2023	951.7	$ 0.6	417.1	1,339.4	(130.5)	(674.9)
Other comprehensive income (loss), unrealized holding gain (loss) on securities arising during period, tax	$ 4.1
Stockholders' equity, shares at Dec. 31, 2023	58,055,968	58,055,968
Stockholders' equity, value at Dec. 31, 2023	$ 1,013.9	$ 0.6	419.8	1,384.3	(86.0)	(704.8)
Stock-based obligations, shares		0
Stock-based obligations, value	2.8	$ 0.0	2.8	0.0	0.0	0.0
Vesting of RSUs and PSUs, net of shares withheld to satisfy minimum tax withholding, shares		111,225
Vesting of RSUs and PSUs, net of shares withheld to satisfy minimum tax withholding, value	(1.7)	$ 0.0	(1.7)	0.0	0.0	0.0
Acquisition of common stock, shares		0
Acquisition of common stock, value	(24.2)	$ 0.0	0.0	0.0	0.0	(24.2)
Dividends declared, shares		0
Dividends declared, value	(14.9)	$ 0.0	0.0	(14.9)	0.0	0.0
Net income	60.0	0.0	0.0	60.0	0.0	0.0
Change in net unrealized gains in investments, net of tax	$ (13.0)	$ 0.0	0.0	0.0	(13.0)	0.0
Stockholders' equity, shares at Jun. 30, 2024	58,167,193	58,167,193
Stockholders' equity, value at Jun. 30, 2024	$ 1,022.9	$ 0.6	420.9	1,429.4	(99.0)	(729.0)
Other comprehensive income (loss), unrealized holding gain (loss) on securities arising during period, tax	3.5
Stockholders' equity, shares at Mar. 31, 2024		58,152,792
Stockholders' equity, value at Mar. 31, 2024	1,018.9	$ 0.6	419.5	1,405.4	(96.9)	(709.7)
Stock-based obligations, shares		0
Stock-based obligations, value	1.4	$ 0.0	1.4	0.0	0.0	0.0
Vesting of RSUs and PSUs, net of shares withheld to satisfy minimum tax withholding, shares		14,401
Vesting of RSUs and PSUs, net of shares withheld to satisfy minimum tax withholding, value	0.0	$ 0.0	0.0	0.0	0.0	0.0
Acquisition of common stock, shares		0
Acquisition of common stock, value	(19.3)	$ 0.0	0.0	0.0	0.0	(19.3)
Dividends declared, shares		0
Dividends declared, value	(7.7)	$ 0.0	0.0	(7.7)	0.0	0.0
Net income	31.7	0.0	0.0	31.7	0.0	0.0
Change in net unrealized gains in investments, net of tax	$ (2.1)	$ 0.0	0.0	0.0	(2.1)	0.0
Stockholders' equity, shares at Jun. 30, 2024	58,167,193	58,167,193
Stockholders' equity, value at Jun. 30, 2024	$ 1,022.9	$ 0.6	$ 420.9	$ 1,429.4	$ (99.0)	$ (729.0)
Other comprehensive income (loss), unrealized holding gain (loss) on securities arising during period, tax	$ 0.7

Valuation of Financial Instruments

6 Months Ended

Jun. 30, 2024

Fair Value of Financial Instruments [Abstract]

Fair Value of Financial Instruments

Valuation of Financial Instruments

Financial Instruments Carried at Fair Value

The carrying value and the estimated fair value of the Company’s financial instruments at fair value were as follows:


	June 30, 2024				December 31, 2023
	Carrying Value		Estimated Fair Value		Carrying Value		Estimated Fair Value
	(in millions)
Financial assets
Total investments at fair value	$	2,272.9	$	2,272.9	$	2,180.6	$	2,180.6
Cash and cash equivalents	95.5		95.5		226.4		226.4
Restricted cash and cash equivalents	0.2		0.2		0.2		0.2

Assets and liabilities recorded at fair value on the Company’s 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.

The Company uses third party pricing services to assist with its investment accounting function. The ultimate pricing source varies depending on the investment security and pricing service used, but investment securities valued on the basis of observable inputs (Levels 1 and 2) are generally assigned values on the basis of actual transactions. Securities valued on the

basis of pricing models with significant unobservable inputs or non-binding broker quotes are classified as Level 3. The Company performs quarterly analyses on the prices it receives 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, as it is ultimately management’s responsibility to ensure that the fair values reflected in the Company’s consolidated financial statements are appropriate. If differences are noted in these analyses, the Company may obtain additional information from other pricing services to validate the quoted price.

The Company bases all of its estimates of fair value for assets on bid prices, when available, as they represent what a third-party market participant would be willing to pay in an arm’s length transaction.

For securities not actively traded, 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 speed assumptions. There were no material adjustments to the valuation methodology utilized by third party pricing services as of June 30, 2024 and December 31, 2023.

These methods of valuation 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.

As of June 30, 2024, the Company held $59.3 million of fixed maturity securities at fair value that were designated Level 3. These private placement securities were designated as Level 3 securities due to the limited amount of observable market information available.

The following table presents the Company’s investments at fair value and the corresponding fair value measurements.


	June 30, 2024						December 31, 2023
	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
	(in millions)
Fixed maturity securities:
U.S. Treasuries	$	—	$	67.6	$	—	$	—	$	58.4	$	—
U.S. Agencies	—		2.2		—		—		2.1		—
States and municipalities	—		185.0		—		—		210.2		—
Corporate securities	—		896.4		45.3		—		863.7		32.1
Residential mortgage-backed securities	—		379.3		—		—		362.2		—
Commercial mortgage-backed securities	—		64.4		—		—		63.8		—
Asset-backed securities	—		163.2		14.0		—		113.9		14.1
Collateralized loan obligations	—		63.5		—		—		91.5		—
Foreign government securities	—		9.8		—		—		10.4		—
Other securities	—		118.7		—		—		113.9		—
Total fixed maturity securities	$	—	$	1,950.1	$	59.3	$	—	$	1,890.1	$	46.2
Equity securities at fair value:
Industrial and miscellaneous	$	202.5	$	—	$	—	$	181.7	$	—	$	—

Other	30.1		—		—		29.5		—		—
Total equity securities at fair value	$	232.6	$	—	$	—	$	211.2	$	—	$	—
Short-term investments	$	9.1	$	21.8	$	—	$	17.6	$	15.5	$	—
Total investments at fair value	$	241.7	$	1,971.9	$	59.3	$	228.8	$	1,905.6	$	46.2

Financial Instruments Carried at Cost

All of the Company's insurance subsidiaries are members of the Federal Home Loan Bank of San Francisco (FHLB). Members are required to purchase stock in the FHLB in addition to maintaining collateral deposits that back any funds advanced and standby letters of credit issued (See Note 10). The Company’s investment in FHLB stock is recorded at cost, which approximates fair value, as purchases and sales of these securities are at par value with the issuer. FHLB stock is considered a restricted security and is periodically evaluated by the Company for impairment based on the estimated ultimate recovery of par value.

Financial Instruments Carried at Net Asset Value

The Company has investments in private equity limited partnership interests that are included in Other invested assets on the Company’s Consolidated Balance Sheets. These investments do not have readily determinable fair values and are carried at net asset value (NAV) and therefore are excluded from the fair value hierarchy. The Company initially estimates the value of these investments using the transaction price. In subsequent periods, the Company measures these investments using NAV per share provided quarterly by the general partner, based on financial statements that are audited annually. These investments are generally not redeemable by the investees and cannot be sold without approval of the general partner. These investments have a fund term of 3 to 12 years, subject to two or three one-year extensions at the general partner’s discretion. The Company will receive distributions of proceeds from dividends and interest from fund investments, as well as from the disposition of a fund investment, or a portion thereof. The Company expects these distributions from time-to-time during the full course of the fund term. As of June 30, 2024, the Company had unfunded commitments to these private equity limited partnerships totaling $18.3 million.

Additionally, certain cash equivalents, principally money market securities, are measured using NAV, which approximates fair value.

The following table presents cash and investments carried at NAV on the Company’s Consolidated Balance Sheets.


	June 30, 2024		December 31, 2023
	(in millions)
Cash equivalents carried at NAV	$	89.3	$	197.2
Other invested assets carried at NAV	97.5		91.5

The following table provides a reconciliation of the beginning and ending balances that are measured using Level 3 inputs.


	Six Months Ended
	June 30,
	2024		2023
	(in millions)
Balance at the beginning of the year	$	46.2	$	24.2
Purchases	13.6		1.0
Unrealized (losses) gains included in comprehensive income or loss	(0.5)		0.2
Balance at end of period	$	59.3	$	25.4

- 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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 6A
-Subparagraph (h)
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 940
-SubTopic 820
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

Valuation of Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2024

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 at fair value were as follows:


	June 30, 2024				December 31, 2023
	Carrying Value		Estimated Fair Value		Carrying Value		Estimated Fair Value
	(in millions)
Financial assets
Total investments at fair value	$	2,272.9	$	2,272.9	$	2,180.6	$	2,180.6
Cash and cash equivalents	95.5		95.5		226.4		226.4
Restricted cash and cash equivalents	0.2		0.2		0.2		0.2

Fair value, assets and liabilities measured on recurring basis table

The following table presents the Company’s investments at fair value and the corresponding fair value measurements.


	June 30, 2024						December 31, 2023
	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
	(in millions)
Fixed maturity securities:
U.S. Treasuries	$	—	$	67.6	$	—	$	—	$	58.4	$	—
U.S. Agencies	—		2.2		—		—		2.1		—
States and municipalities	—		185.0		—		—		210.2		—
Corporate securities	—		896.4		45.3		—		863.7		32.1
Residential mortgage-backed securities	—		379.3		—		—		362.2		—
Commercial mortgage-backed securities	—		64.4		—		—		63.8		—
Asset-backed securities	—		163.2		14.0		—		113.9		14.1
Collateralized loan obligations	—		63.5		—		—		91.5		—
Foreign government securities	—		9.8		—		—		10.4		—
Other securities	—		118.7		—		—		113.9		—
Total fixed maturity securities	$	—	$	1,950.1	$	59.3	$	—	$	1,890.1	$	46.2
Equity securities at fair value:
Industrial and miscellaneous	$	202.5	$	—	$	—	$	181.7	$	—	$	—

Other	30.1		—		—		29.5		—		—
Total equity securities at fair value	$	232.6	$	—	$	—	$	211.2	$	—	$	—
Short-term investments	$	9.1	$	21.8	$	—	$	17.6	$	15.5	$	—
Total investments at fair value	$	241.7	$	1,971.9	$	59.3	$	228.8	$	1,905.6	$	46.2

Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Table Text Block]

Financial Instruments Carried at Net Asset Value

Additionally, certain cash equivalents, principally money market securities, are measured using NAV, which approximates fair value.

The following table presents cash and investments carried at NAV on the Company’s Consolidated Balance Sheets.


	June 30, 2024		December 31, 2023
	(in millions)
Cash equivalents carried at NAV	$	89.3	$	197.2
Other invested assets carried at NAV	97.5		91.5

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation

The following table provides a reconciliation of the beginning and ending balances that are measured using Level 3 inputs.


	Six Months Ended
	June 30,
	2024		2023
	(in millions)
Balance at the beginning of the year	$	46.2	$	24.2
Purchases	13.6		1.0
Unrealized (losses) gains included in comprehensive income or loss	(0.5)		0.2
Balance at end of period	$	59.3	$	25.4

- Definition

Tabular disclosure of the fair value measurement of assets using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets) and gains or losses recognized in other comprehensive income (loss), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs), by class of asset.

+ References + Details

Segment Reporting (Tables)

6 Months Ended

Jun. 30, 2024

Net Income before income taxes by segment [Abstract]

Schedule of Segment Reporting Information, by Segment [Table Text Block]


	Insurance Operations		Total
	(in millions)
Three Months Ended June 30, 2024
Gross premiums written	$	207.9	$	207.9
Net premiums written	206.1		206.1

Net premiums earned	187.8		187.8
Net investment income	26.9		26.9
Net realized and unrealized gains on investments	2.2		2.2

Other income	0.1		0.1
Total revenues	217.0		217.0

Losses and loss adjustment expenses	108.8		108.8
Commission expense	26.8		26.8
Underwriting and general and administrative expenses	41.4		41.4


Total expenses	177.0		177.0

Net income before income taxes	40.0		40.0
Income tax expense	8.3		8.3
Net income	$	31.7	$	31.7

Three Months Ended June 30, 2023
Gross premiums written	$	198.4	$	198.4
Net premiums written	196.6		196.6

Net premiums earned	177.1		177.1
Net investment income	26.8		26.8
Net realized and unrealized gains on investments	11.3		11.3


Total revenues	215.2		215.2

Losses and loss adjustment expenses	90.5		90.5
Commission expense	23.6		23.6
Underwriting and general and administrative expenses	46.0		46.0
Interest and financing expenses	1.9		1.9
Other expenses	9.4		9.4
Total expenses	171.4		171.4

Net income before income taxes	43.8		43.8
Income tax expense	8.9		8.9
Net income	$	34.9	$	34.9


	Insurance Operations		Total
	(in millions)
Six Months Ended June 30, 2024
Gross premiums written	$	418.7	$	418.7
Net premiums written	415.2		415.2

Net premiums earned	372.6		372.6
Net investment income	53.8		53.8
Net realized and unrealized gains on investments	13.6		13.6

Other income	0.1		0.1
Total revenues	440.1		440.1

Losses and loss adjustment expenses	225.3		225.3
Commission expense	52.3		52.3
Underwriting and general and administrative expenses	87.2		87.2


Total expenses	364.8		364.8

Net income before income taxes	$	75.3	$	75.3
Income tax expense	15.3		15.3
Net income	$	60.0	$	60.0


Six Months Ended June 30, 2023
Gross premiums written	$	393.3	$	393.3
Net premiums written	389.7		389.7

Net premiums earned	349.8		349.8
Net investment income	54.4		54.4
Net realized and unrealized gains on investments	17.7		17.7

Other income (loss)	(0.2)		(0.2)
Total revenues	421.7		421.7

Losses and loss adjustment expenses	197.9		197.9
Commission expense	47.1		47.1
Underwriting and general and administrative expenses	90.3		90.3
Interest and financing expenses	4.2		4.2
Other expenses	9.4		9.4
Total expenses	348.9		348.9

Net income before income taxes	72.8		72.8
Income tax expense	14.3		14.3
Net income	$	58.5	$	58.5

Revenue from External Customers by Geographic Areas [Table Text Block]


	June 30, 2024			December 31, 2023			June 30, 2023			December 31, 2022
State	In-force Premiums		Policies In-force	In-force Premiums		Policies In-force	In-force Premiums		Policies In-force	In-force Premiums		Policies In-force
	(dollars in millions)
California	$	328.0	43,965	$	311.5	43,353	$	291.0	43,133	$	279.7	42,876
Florida	58.0		10,490	56.6		10,008	53.0		9,790	49.4		9,417
New York	34.9		7,913	31.9		7,603	30.6		7,552	27.3		7,497


Other (43 states and D.C.)	308.4		66,154	294.6		65,445	278.8		64,373	266.1		61,566
Total in-force	$	729.3	128,522	$	694.6	126,409	$	653.4	124,848	$	622.5	121,356
Estimated audit premium	40.0		—	34.9		—	31.2		—	31.5		—
Total in-force, including estimated audit premium	$	769.3	128,522	$	729.5	126,409	$	684.6	124,848	$	654.0	121,356

Investments, Amortized Cost and Estimated Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Amortized Cost
Due in one year or less, amortized cost	$ 46.3
Due after one year through five years, amortized cost	644.6
Due after five years through ten years, amortized cost	613.0
Due after ten years, amortized cost	93.7
Mortgage and asset-backed securities, amortized cost	739.0
Debt securities, available-for-sale, amortized cost	2,136.6	$ 2,048.0
Estimated Fair Value
Due in one year or less, fair value	45.6
Due after one year through five years, fair value	622.5
Due after five years through ten years, fair value	571.7
Due after ten years, fair value	85.2
Mortgage and asset-backed securities, fair value	684.4
Total, fair value	$ 2,009.4	$ 1,936.3

Income Taxes	6 Months Ended
Income Taxes	Jun. 30, 2024
Income Taxes [Abstract]
Income Taxes	Income Taxes The Company’s effective tax rate for the three and six months ended June 30, 2024 was 20.8% and 20.3%, respectively, and the Company’s effective tax rate for the three and six months ended June 30, 2023 was 20.3% and 19.6%, respectively. The effective rates during each of the periods presented included income tax benefits and exclusions associated with tax-advantaged investment income, LPT adjustments, and deferred gain amortization. The Inflation Reduction Act of 2022 imposed a 1% excise tax on stock repurchases by publicly traded companies, effective January 1, 2023. The Company's excise tax obligation during the six months ended June 30, 2024 was $0.2 million and $0.7 million during the year ended December 31, 2023, respectively, which is included in Treasury stock on its Consolidated Balance Sheets.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-231

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12C

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477891/740-270-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-13

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/740/tableOfContent

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-14

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-21

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-17

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

LPT Agreement (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
LPT Agreement (Details) - USD ($) $ in Millions	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Reinsurance Agreement [Line Items]
Amortization of deferred gain	$ 1.9	$ 2.0	$ 3.8	$ 4.0
LPT Contingent Commission Adjustment [Abstract]	0.2		0.4
Impact of the LPT Agreement	2.1	$ 2.0	4.2	$ 4.0
Deferred reinsurance gain—LPT Agreement	95.3		95.3		$ 99.2
Estimated remaining liabilities - LPT Agreement	282.6		282.6		291.7
Paid losses and LAE claims related to LPT	886.7		886.7		$ 877.6
Indemnification Agreement [Member]
Reinsurance Agreement [Line Items]
Coverage provided under LPT Agreement	$ 2,000.0		$ 2,000.0

Earnings Per Share

6 Months Ended

Jun. 30, 2024

Earnings Per Share [Abstract]

Earnings Per Share

Earnings Per Common Share

Basic earnings per share is computed by dividing net income by the weighted average number of common shares outstanding for the period. Diluted earnings per share reflects the potential dilutive impact of all common stock equivalents on earnings per share. Diluted earnings per share includes common shares assumed issued under the “treasury stock method,” which reflects the potential dilution that would occur if outstanding RSUs and PSUs vested.

No outstanding PSUs and RSUs are considered in the Company’s diluted earnings per share computations in any period that involves a net loss because their inclusion would be anti-dilutive.

Employees who are awarded RSUs and PSUs are entitled to receive dividend equivalents for eligible awards, payable in cash, when and if, the underlying award vests and becomes payable. Therefore, these awards are not considered participating securities for the purposes of determining earnings per share.

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


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions, except share data)
Net income	$	31.7	$	34.9	$	60.0	$	58.5
Weighted average number of shares outstanding—basic	25,278,473		26,691,652		25,312,208		26,932,897
Effect of dilutive securities:
PSUs	47,684		85,691		81,353		113,469
Stock options	—		—		—		4,143
RSUs	37,784		25,997		56,396		46,160
Potential dilutive shares	85,468		111,688		137,749		163,772
Weighted average number of shares outstanding—diluted	25,363,941		26,803,340		25,449,957		27,096,669

Property and Equipment Leases, Maturities of Lease Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Lessee, operating lease liabilities due
Operating lease liabilities due next twelve months	$ 0.9
Operating lease liabilities due year two	1.5
Operating lease liabilities due year three	1.2
Operating lease liabilities due year four	1.2
Operating lease liabilities due year five	0.4
Operating lease liabilities due after year five	0.0
Operating lease liabilities due	5.2
Less: inputed interest, Operating lease liability	(0.1)
Operating lease liability	$ 5.1	$ 5.9
Operating lease, weighted average remaining lease term	3 years 7 months 6 days
Operating lease, weighted average discount rate, percent	1.30%
Lessee, finance lease liabilities due
Finance lease liabilities due next twelve months	$ 0.0
Finance lease liabilities due year two	0.1
Finance lease liabilities due year three	0.0
Finance lease liabilities due year four	0.0
Finance lease liabilities due year five	0.0
Finance lease liabilities due after year five	0.0
Finance lease liabilities due	0.1
Less: inputed interest, finance lease	0.0
Finance lease, liability	$ 0.1	$ 0.2
Finance lease, weighted average remaining lease term	1 year 7 months 6 days
Finance lease, weighted average discount rate, percent	7.40%

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2024

Stock-Based Compensation [Abstract]

Share-based compensation arrangements by share-based payment award table

The Company awarded restricted stock units (RSUs) and performance share units (PSUs) to certain employees and non-employee Directors of the Company as follows:


	Number Awarded	Weighted Average Fair Value on Date of Grant	Aggregate Fair Value on Date of Grant
			(in millions)
February 2024
RSUs(1)	61,280	46.36	2.8
PSUs(2)	77,360	46.36	3.6

March 2024
RSUs(1)	4,712	45.00	0.2

May 2024


RSUs(3)	17,052	40.00	0.7

(1)These RSUs were awarded to certain employees of the Company on two separate dates and all vest 25% on March 15, 2025 and each of the subsequent three anniversaries of that date.

(3)All RSUs awarded on this date were awarded to non-employee directors of the Company and vest in full on May 23, 2025.

Investments, Continuous Loss Position (Details) $ in Millions	Jun. 30, 2024 USD ($) shares shares	Dec. 31, 2023 USD ($) shares
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 319.7	$ 129.9
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,200.2	1,291.6
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3.0)	(1.6)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (130.2)	$ (122.3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, less than 12 months \| shares	220	133
Debt Securities, number of issues in loss position, 12 months or greater	650	733
Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 319.7	$ 129.9
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,200.2	1,291.6
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3.0)	(1.6)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (130.2)	$ (122.3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, less than 12 months \| shares	220	133
Debt Securities, number of issues in loss position, 12 months or greater \| shares	650	733
US Treasury Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 20.1	$ 11.9
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	34.8	23.7
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(0.1)	(0.1)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (2.9)	$ (2.4)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, less than 12 months \| shares	7	5
Debt Securities, number of issues in loss position, 12 months or greater	11	7
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 2.2	$ 2.2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (0.1)	$ (0.1)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, 12 months or greater	1	1
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 33.0	$ 39.5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	83.6	73.5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(0.5)	(0.3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (5.3)	$ (4.9)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, less than 12 months \| shares	13	15
Debt Securities, number of issues in loss position, 12 months or greater	36	32
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 134.6	$ 26.1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	666.7	684.5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1.4)	(0.8)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (64.3)	$ (62.4)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, less than 12 months \| shares	36	13
Debt Securities, number of issues in loss position, 12 months or greater	282	331
Residential Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 42.4	$ 15.8
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	293.6	306.6
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(0.3)	(0.2)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (45.1)	$ (37.8)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, less than 12 months \| shares	25	15
Debt Securities, number of issues in loss position, 12 months or greater	234	228
Commercial Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 52.5	$ 53.0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (5.6)	$ (6.4)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, 12 months or greater	23	24
Asset-backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 66.3	$ 24.0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	48.6	47.0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(0.4)	(0.1)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (3.8)	$ (4.7)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, less than 12 months \| shares	22	15
Debt Securities, number of issues in loss position, 12 months or greater	36	29
Collateralized Loan Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0.0	$ 0.0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	5.4	80.5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0.0	0.0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (0.1)	$ (0.7)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, less than 12 months \| shares	0	0
Debt Securities, number of issues in loss position, 12 months or greater \| shares	3	21
Foreign Government Debt
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 9.8	$ 10.4
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (2.9)	$ (2.3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, 12 months or greater \| shares	2	2
Other Debt Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 23.3	$ 12.6
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	3.0	10.2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(0.3)	(0.1)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (0.1)	$ (0.6)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Debt Securities, number of issues in loss position, less than 12 months \| shares	117	70
Debt Securities, number of issues in loss position, 12 months or greater \| shares	22	58

Liability for Unpaid Losses and Loss Adjustment Expenses (Tables)

6 Months Ended

Jun. 30, 2024

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.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Unpaid losses and LAE at beginning of period	$	1,874.5	$	1,953.7	$	1,884.5	$	1,960.7
Less reinsurance recoverable, excluding CECL allowance, on unpaid losses and LAE	424.0		440.3		428.4		445.4
Net unpaid losses and LAE at beginning of period	1,450.5		1,513.4		1,456.1		1,515.3
Losses and LAE, net of reinsurance, incurred during the period related to:
Current period	120.0		112.2		238.7		221.8
Prior periods	(9.1)		(19.7)		(9.2)		(19.9)
Total net losses and LAE incurred during the period	110.9		92.5		229.5		201.9
Paid losses and LAE, net of reinsurance, related to:
Current period	24.1		26.5		30.9		32.1
Prior periods	104.7		88.4		222.1		194.1
Total net paid losses and LAE during the period	128.8		114.9		253.0		226.2
Ending unpaid losses and LAE, net of reinsurance	1,432.6		1,491.0		1,432.6		1,491.0
Reinsurance recoverable, excluding CECL allowance, on unpaid losses and LAE	418.3		436.2		418.3		436.2
Unpaid losses and LAE at end of period	$	1,850.9	$	1,927.2	$	1,850.9	$	1,927.2

Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Operating activities
Net income	$ 31.7	$ 34.9	$ 60.0	$ 58.5
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization			1.9	2.7
Stock-based compensation			2.8	3.2
Amortization of cloud computing arrangements	4.5		7.3	8.4	$ 16.7
Amortization of discounts and premiums on investments, net			(0.7)	1.8
Allowance for expected credit losses			0.9	2.4
Deferred income tax (benefit) expense			4.8	4.9
Net realized and unrealized gains on investments			(13.6)	(17.7)
Asset Impairment Charges		2.6	0.0	2.6
Gain (Loss) on Termination of Lease		(1.0)	0.0	(1.0)
Change in operating assets and liabilities:
Premiums receivable			(41.3)	(48.8)
Reinsurance recoverable on paid and unpaid losses			10.1	9.2
Cloud computing arrangements			(0.4)	(2.2)
Operating lease right-of-use assets			0.7	6.9
Current federal income taxes			(4.6)	(11.9)
Unpaid losses and loss adjustment expenses			(33.6)	(33.5)
Unearned premiums			39.7	39.0
Accounts payable, accrued expenses and other liabilities			(2.4)	(5.6)
Deferred reinsurance gain—LPT Agreement			(3.9)	(4.0)
Contingent commission receivable—LPT Agreement			(0.4)	0.0
Operating lease liabilities			(0.8)	(7.2)
Non-cancellable obligations			(4.9)	(5.7)
Other			(9.3)	(5.5)
Net cash provided by (used in) operating activities			12.3	(3.5)
Investing activities
Purchases of fixed maturity securities			(274.7)	(157.8)
Payments to Acquire Equity Securities, FV-NI			(22.0)	(22.6)
Purchases of short-term investments			(17.7)	(24.5)
Purchases of other invested assets			(4.1)	(20.6)
Proceeds from sale of fixed maturity securities	52.7	80.7	84.7	125.5
Proceeds from Sale of Equity Securities, FV-NI			17.1	32.5
Proceeds from maturities and redemptions of fixed maturity securities			96.5	63.8
Proceeds from maturities of short-term investments			20.2	127.3
Net change in unsettled investment purchases and sales			0.7	(3.6)
Capital expenditures and other			(2.3)	(0.6)
Net cash (used in) provided by investing activities			(101.6)	119.4
Financing activities
Acquisition of common stock			(24.4)	(46.1)
Cash transactions related to stock-based compensation			(1.7)	(0.7)
Dividends paid to stockholders			(15.4)	(15.2)
Repayments of FHLBank Advance, Investing Activities			0.0	(76.8)
Financing cash flows from finance leases			(0.1)	(0.1)
Net cash used in financing activities			(41.6)	(138.9)
Net decrease in cash, cash equivalents and restricted cash			(130.9)	(23.0)
Cash, cash equivalents, restricted cash and restricted cash equivalents at the beginning of the period			226.6	89.4	89.4
Cash, cash equivalents, restricted cash and restricted cash equivalents at the end of the period	95.7	66.4	95.7	66.4	226.6
Cash and cash equivalents	95.5		95.5		226.4
Restricted cash and cash equivalents	0.2		0.2		0.2
Total cash, cash equivalents, restricted cash	$ 95.7	$ 66.4	$ 95.7	$ 66.4	$ 226.6

Basis of Presentation (Details) - USD ($) $ in Millions	6 Months Ended
Basis of Presentation (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Reinsurance Agreement [Line Items]
Reinsurance Quota Share, Percentage	100.00%
Contingent commission receivable—LPT Agreement	$ 14.6	$ 14.2
Indemnification Agreement [Member]
Reinsurance Agreement [Line Items]
Coverage provided under LPT Agreement	$ 2,000.0

LPT Agreement	6 Months Ended
LPT Agreement	Jun. 30, 2024
LPT Agreement [Abstract]
LPT Agreement	LPT Agreement The LPT Agreement, which ceded to the reinsurers substantially all of the Fund's outstanding losses as of June 30, 1999 for claims with original dates of injury prior to July 1, 1995, provides coverage for losses up to $2.0 billion, excluding losses for burial and transportation expenses. The Company records its estimate of the associated contingent profit commission in its Consolidated Balance Sheets as Contingent commission receivable–LPT Agreement and a corresponding liability is recorded in its Consolidated Balance Sheets in Deferred reinsurance gain–LPT Agreement. The Deferred Gain is being amortized using the recovery method. Amortization is determined by the proportion of actual reinsurance recoveries to total estimated recoveries over the life of the LPT Agreement, except for the contingent profit commission, which is amortized through June 30, 2024, the date through which the Company is entitled to receive a contingent profit commission under the LPT Agreement. The amortization is recorded in losses and LAE incurred in its Consolidated Statements of Comprehensive Income (Loss). Any adjustments to the Deferred Gain are recorded in losses and LAE incurred in its Consolidated Statements of Comprehensive Income (Loss). The Company amortized $1.9 million and $2.0 million of the Deferred Gain for the three months ended June 30, 2024 and 2023, respectively, and $3.8 million and $4.0 million for the six months ended June 30, 2024 and 2023. The remaining Deferred Gain was $95.3 million and $99.2 million as of June 30, 2024 and December 31, 2023, respectively. Additionally, the Company recognized $0.2 million and $0.4 million of favorable LPT Contingent Commission Adjustments for the three and six months ended June 30, 2024, respectively. The estimated remaining liabilities subject to the LPT Agreement were $282.6 million and $291.7 million as of June 30, 2024 and December 31, 2023, respectively. Losses and LAE paid with respect to the LPT Agreement totaled $886.7 million and $877.6 million from inception through June 30, 2024 and December 31, 2023, respectively.

Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Accumulated Other Comprehensive Income [Abstract]
Net unrealized losses on AFS investments, before taxes	$ (125.3)	$ (108.9)
Deferred tax benefit on net unrealized losses	26.3	22.9
Total accumulated other comprehensive loss	$ (99.0)	$ (86.0)

- Definition

Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

+ References + Details

Property and Equipment Property and Equipment (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended		12 Months Ended
	Jun. 30, 2024	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Property and Equipment [Line Items]
Property and equipment, gross	$ 46.2	$ 46.2		$ 48.6
Accumulated depreciation, depletion and amortization, property and equipment	(39.5)	(39.5)		(42.1)
Property and equipment, net	6.7	6.7		6.5
Utilities operating expense, depreciation and amortization	0.9	1.9		4.8
Payments to develop software	0.7	1.3		1.8
Cloud computing arrangements	21.2	21.2		28.0
Amortization of cloud computing arrangements	4.5	7.3	$ 8.4	16.7
Furniture and equipment
Property and Equipment [Line Items]
Property and equipment, gross	1.8	1.8		1.8
Leasehold improvements
Property and Equipment [Line Items]
Property and equipment, gross	0.5	0.5		0.5
Computer and software
Property and Equipment [Line Items]
Property and equipment, gross	43.3	43.3		45.7
Automobiles
Property and Equipment [Line Items]
Property and equipment, gross	$ 0.6	$ 0.6		$ 0.6

Investments Equity Securities (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Schedule of Equity Securities and Other [Line Items]
Equity Securities, FV-NI, Cost	$ 134.4	$ 125.9
Equity Securities, FV-NI	232.6	211.2
Industrial and Miscellaneous [Member]
Schedule of Equity Securities and Other [Line Items]
Equity Securities, FV-NI, Cost	111.5	104.4
Equity Securities, FV-NI	202.5	181.7
Other [Member]
Schedule of Equity Securities and Other [Line Items]
Equity Securities, FV-NI, Cost	22.9	21.5
Equity Securities, FV-NI	$ 30.1	$ 29.5

Property and Equipment (Tables)

6 Months Ended

Jun. 30, 2024

Property, Plant and Equipment [Abstract]

Property and Equipment [Table Text Block]

Property and equipment consists of the following:


	As of June 30,		As of December 31,
	2024		2023
	(in millions)

Furniture and equipment	$	1.8	$	1.8
Leasehold improvements	0.5		0.5
Computers and software	43.3		45.7
Automobiles	0.6		0.6
Property and equipment, gross	46.2		48.6
Accumulated depreciation	(39.5)		(42.1)
Property and equipment, net	$	6.7	$	6.5

Lease, Cost [Table Text Block]

Components of lease expense were as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2024		2023		2024		2023
	(in millions)
Operating lease expense	$	0.2	$	0.5	$	0.5	$	1.1



Finance lease expense	0.1		—		0.1		0.1
Total lease expense	$	0.3	$	0.5	$	0.6	$	1.2

Lessee, Operating and Finance Lease Liability Maturity [Table Text Block]

Maturities of lease liabilities were as follows:


	As of June 30, 2024
	Operating Leases		Finance Leases
	(in millions)
2024	$	0.9	$	—
2025	1.5		0.1
2026	1.2		—
2027	1.2		—
2028	0.4		—
Thereafter	—		—
Total lease payments	5.2		0.1
Less: imputed interest	(0.1)		—
Total	$	5.1	$	0.1

Supplemental Balance Sheet Information related to Leases [Table Text Block]

Supplemental balance sheet information related to leases was as follows:


	As of June 30,		As of December 31,
	2024		2023
	(in millions)
Operating leases:
Operating lease right-of-use asset	$	4.4	$	5.1
Operating lease liability	5.1		5.9
Finance leases:
Property and equipment, gross	0.6		0.6
Accumulated depreciation	(0.5)		(0.4)
Property and equipment, net	0.1		0.2
Other liabilities	$	0.1	$	0.2

Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]

Supplemental cash flow information related to leases was as follows:


	Six Months Ended
	June 30,
	2024		2023
	(in millions)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows used for operating leases	$	0.5	$	1.1

Financing cash flows used for finance leases	0.1		0.1

Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Consolidated Statements of Income - USD ($) $ in Millions	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Revenues
Net premiums earned	$ 187.8	$ 177.1	$ 372.6	$ 349.8
Net investment income	26.9	26.8	53.8	54.4
Net Realized and Unrealized (Losses) Gains on Investments	2.2	11.3	13.6	17.7
Other income (loss)	0.1		0.1	(0.2)
Total revenues	217.0	215.2	440.1	421.7
Expenses
Losses and loss adjustment expenses	108.8	90.5	225.3	197.9
Commission expense	26.8	23.6	52.3	47.1
Underwriting and general and administrative expenses	41.4	46.0	87.2	90.3
Interest and financing expenses		1.9		4.2
Other Expenses		9.4		9.4
Total expenses	177.0	171.4	364.8	348.9
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest, Total	40.0	43.8	75.3	72.8
Income tax expense	8.3	8.9	15.3	14.3
Net Income	31.7	34.9	60.0	58.5
Comprehensive income
Unrealized AFS investment (losses) gains arising during the period, net of tax benefit (expense) of $1.4 and $4.1 for the three months ended June 30, 2024 and 2023, respectively, and $4.4 and $(1.9) for the six months ended June 30, 2024 and 2023, respectively	(4.9)	(15.5)	(16.5)	7.1
Reclassification adjustment for realized AFS investment losses in net income, net of tax benefit of $(0.7) for the three months ended June 30, 2024, and $(0.9) and $(0.4) for the six months ended June 30, 2024 and 2023, respectively	2.8	0.1	3.5	1.3
Other comprehensive (loss) income, net of tax	(2.1)	(15.4)	(13.0)	8.4
Total Comprehensive income	$ 29.6	$ 19.5	$ 47.0	$ 66.9
Earnings per common share (Note 13):
Basic	$ 1.25	$ 1.31	$ 2.37	$ 2.17
Diluted	1.25	1.30	2.36	2.16
Cash dividends declared per common share and eligible plan awards	$ 0.30	$ 0.28	$ 0.58	$ 0.54

Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Net Investment Income (Details) - USD ($) $ in Millions	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 27.8	$ 27.5	$ 55.7	$ 56.0
Investment expenses	0.9	0.7	1.9	1.6
Net investment income	26.9	26.8	53.8	54.4
Debt Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	23.1	23.4	45.4	47.1
Equity Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	1.7	1.8	3.3	3.6
Other Investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	1.4	0.9	2.6	1.8
Short-term Investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	0.4	0.5	0.9	1.7
Cash and Cash Equivalents [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income	$ 1.2	$ 0.9	$ 3.5	$ 1.8

Segment Reporting Geographic Information (Details) $ in Millions	6 Months Ended
	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Revenue, Major Customer [Line Items]
Segment Reporting, Disclosure of Major Customers	10
CALIFORNIA
Revenue, Major Customer [Line Items]
Premiums In Force	$ 328.0	$ 311.5	$ 291.0	$ 279.7
Policies In force	43,965	43,353	43,133	42,876
FLORIDA
Revenue, Major Customer [Line Items]
Premiums In Force	$ 58.0	$ 56.6	$ 53.0	$ 49.4
Policies In force	10,490	10,008	9,790	9,417
NEW YORK
Revenue, Major Customer [Line Items]
Premiums In Force	$ 34.9	$ 31.9	$ 30.6	$ 27.3
Policies In force	7,913	7,603	7,552	7,497
AllOtherStates [Member]
Revenue, Major Customer [Line Items]
Premiums In Force	$ 308.4	$ 294.6	$ 278.8	$ 266.1
Policies In force	66,154	65,445	64,373	61,566
UNITED STATES
Revenue, Major Customer [Line Items]
Premiums In Force	$ 729.3	$ 694.6	$ 653.4	$ 622.5
Policies In force	128,522	126,409	124,848	121,356
Final audit policies in-force	0	0	0	0
Final audit premium	$ 40.0	$ 34.9	$ 31.2	$ 31.5
Total in-force policies, includingfinal audit	128,522	126,409	124,848	121,356
Total in-force, including final audit premium	$ 769.3	$ 729.5	$ 684.6	$ 654.0

Property and Equipment Leases, Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Leases, Supplement Balance Sheet Information [Abstract]
Operating cash flows from operating leases	$ 0.5	$ 1.1
Financing cash flows from finance leases	$ 0.1	$ 0.1

Property and Equipment Leases, Components of Lease Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Components of Lease Expense [Abstract]
Operating Lease, Cost			$ 0.5	$ 1.1
Operating lease expense	$ 0.2	$ 0.5
Finance lease expense	0.1	0.0	0.1	0.1
Total lease expense	$ 0.3	$ 0.5	$ 0.6	$ 1.2