RLI (RLI) 10-Q 23 Oct 24 2024 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2024	Oct. 15, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Sep. 30, 2024
Entity File Number	001-09463
Entity Registrant Name	RLI Corp
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	37-0889946
Entity Address, Address Line One	9025 North Lindbergh Drive,
Entity Address, City or Town	Peoria,
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	61615
City Area Code	309
Local Phone Number	692-1000
Title of 12(b) Security	Common Stock $0.01 par value
Trading Symbol	RLI
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		45,821,466
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Entity Central Index Key	0000084246
Amendment Flag	false

Condensed Consolidated Statemen

Condensed Consolidated Statements of Earnings and Comprehensive Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Statement [Abstract]
Net premiums earned	$ 389,489	$ 318,409	$ 1,129,230	$ 948,412
Net investment income	36,694	31,963	103,502	87,835
Net realized gains	5,420	6,558	11,222	26,758
Net unrealized gains (losses) on equity securities	38,392	(25,236)	87,314	15,474
Consolidated revenue	469,995	331,694	1,331,268	1,078,479
Losses and settlement expenses	202,118	189,558	513,741	457,989
Policy acquisition costs	117,811	103,013	342,186	307,083
Insurance operating expenses	28,868	21,591	84,892	70,002
Interest expense on debt	1,617	1,873	4,839	5,928
General corporate expenses	3,994	2,372	13,144	10,805
Total expenses	354,408	318,407	958,802	851,807
Equity in earnings of unconsolidated investees	1,238	1,732	7,653	7,169
Earnings (loss) before income taxes	116,825	15,019	380,119	233,841
Income tax expense	21,798	1,483	75,200	43,842
Net earnings (loss)	95,027	13,536	304,919	189,999
Other comprehensive earnings (loss), net of tax	80,293	(56,834)	59,779	(38,848)
Comprehensive earnings (loss)	$ 175,320	$ (43,298)	$ 364,698	$ 151,151
Basic net earnings per share	$ 2.08	$ 0.30	$ 6.67	$ 4.17
Diluted net earnings per share	$ 2.06	$ 0.29	$ 6.60	$ 4.12
Weighted average number of common shares outstanding:
Basic	45,780	45,622	45,734	45,581
Diluted	46,220	46,065	46,185	46,067

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
ASSETS
Available-for-sale, at fair value (amortized cost of $3,302,684 and allowance for credit losses of $234 at 9/30/24) (amortized cost of $3,054,391 and allowance for credit losses of $306 at 12/31/23)	$ 3,176,073	$ 2,855,849
Equity securities, at fair value (cost - $405,663 at 9/30/24 and $354,022 at 12/31/23)	729,738	590,041
Short-term investments, at cost which approximates fair value	203,296	134,923
Other invested assets	53,993	59,081
Cash	60,634	36,424
Total investments and cash	4,223,734	3,676,318
Accrued investment income	26,711	24,062
Premiums and reinsurance balances receivable, net of allowances for uncollectible amounts of $22,049 at 9/30/24 and $21,438 at 12/31/23	241,311	221,206
Ceded unearned premium	120,845	112,257
Reinsurance balances recoverable on unpaid losses and settlement expenses, net of allowances for uncollectible amounts of $10,055 at 9/30/24 and $10,608 at 12/31/23	759,540	757,349
Deferred policy acquisition costs	172,069	146,566
Property and equipment, at cost, net of accumulated depreciation of $74,821 at 9/30/24 and $74,279 at 12/31/23	44,644	46,715
Investment in unconsolidated investees	65,271	56,966
Goodwill and intangibles	53,562	53,562
Income taxes-deferred		15,872
Other assets	84,068	69,348
TOTAL ASSETS	5,791,755	5,180,221
Liabilities
Unpaid loss and settlement expenses	2,611,941	2,446,025
Unearned premiums	1,010,760	892,326
Reinsurance balances payable	43,423	71,507
Funds held	98,585	101,446
Income taxes-current	4,369	3,757
Income taxes-deferred	15,369
Debt	100,000	100,000
Accrued expenses	105,813	108,880
Other liabilities	53,145	42,766
TOTAL LIABILITIES	4,043,405	3,766,707
Shareholders' Equity
Common stock ($0.01 par value) (Shares authorized - 200,000,000) (68,740,134 shares issued, 45,809,920 shares outstanding at 9/30/24) (68,570,261 shares issued, 45,640,047 shares outstanding at 12/31/23)	687	686
Paid-in capital	371,398	362,345
Accumulated other comprehensive earnings (loss)	(106,524)	(166,303)
Retained earnings	1,875,788	1,609,785
Deferred compensation	11,917	13,539
Less: Treasury shares, at cost (22,930,214 shares at 9/30/24 and 12/31/23)	(404,916)	(406,538)
TOTAL SHAREHOLDERS' EQUITY	1,748,350	1,413,514
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 5,791,755	$ 5,180,221

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Statement Of Financial Position [Abstract]
Available-for-sale, amortized cost	$ 3,302,684	$ 3,054,391
Available-for-sale, allowance for credit losses	234	306
Equity securities, cost	405,663	354,022
Premiums and reinsurance balances receivable, allowances for uncollectible amounts	22,049	21,438
Reinsurance balances recoverable on unpaid losses and settlement expenses, allowances for uncollectible amounts	10,055	10,608
Property and equipment, accumulated depreciation	$ 74,821	$ 74,279
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	68,740,134	68,570,261
Common stock, shares outstanding (in shares)	45,809,920	45,640,047
Treasury stock, shares (in shares)	22,930,214	22,930,214

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Common stock	Paid-in Capital	Accumulated Other Comprehensive Earnings (Loss)	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings	Deferred Compensation	Treasury Stock at Cost	Cumulative Effect, Period of Adoption, Adjustment	Total
Shareholders' Equity Attributable to Parent, Beginning Balance at Dec. 31, 2022	$ 684	$ 352,391	$ (229,076)	$ (951)	$ 1,446,341	$ 12,015	$ (405,014)	$ (951)	$ 1,177,341
Shares, Outstanding, Beginning Balance at Dec. 31, 2022	45,469,752
Increase Decrease In Shareholders Equity Roll Forward
Net Income (Loss)					98,811				98,811
Other comprehensive earnings (loss), net of tax			37,707						37,707
Deferred compensation						249	(249)
Share-based compensation	$ 1	2,863							2,864
Share-based compensation (in shares)	84,944
Dividends and dividend equivalents					(11,851)				(11,851)
Shareholders' Equity Attributable to Parent, Ending Balance at Mar. 31, 2023	$ 685	355,254	(191,369)		1,532,350	12,264	(405,263)		1,303,921
Shares, Outstanding, Ending Balance at Mar. 31, 2023	45,554,696
Shareholders' Equity Attributable to Parent, Beginning Balance at Dec. 31, 2022	$ 684	352,391	(229,076)	$ (951)	1,446,341	12,015	(405,014)	$ (951)	1,177,341
Shares, Outstanding, Beginning Balance at Dec. 31, 2022	45,469,752
Increase Decrease In Shareholders Equity Roll Forward
Net Income (Loss)									189,999
Other comprehensive earnings (loss), net of tax									(38,848)
Shareholders' Equity Attributable to Parent, Ending Balance at Sep. 30, 2023	$ 686	360,453	(267,924)		1,598,875	12,617	(405,616)		1,299,091
Shares, Outstanding, Ending Balance at Sep. 30, 2023	45,625,771
Shareholders' Equity Attributable to Parent, Beginning Balance at Mar. 31, 2023	$ 685	355,254	(191,369)		1,532,350	12,264	(405,263)		1,303,921
Shares, Outstanding, Beginning Balance at Mar. 31, 2023	45,554,696
Increase Decrease In Shareholders Equity Roll Forward
Net Income (Loss)					77,652				77,652
Other comprehensive earnings (loss), net of tax			(19,721)						(19,721)
Deferred compensation						243	(243)
Share-based compensation		2,402							2,402
Share-based compensation (in shares)	41,500
Dividends and dividend equivalents					(12,342)				(12,342)
Shareholders' Equity Attributable to Parent, Ending Balance at Jun. 30, 2023	$ 685	357,656	(211,090)		1,597,660	12,507	(405,506)		1,351,912
Shares, Outstanding, Ending Balance at Jun. 30, 2023	45,596,196
Increase Decrease In Shareholders Equity Roll Forward
Net Income (Loss)					13,536				13,536
Other comprehensive earnings (loss), net of tax			(56,834)						(56,834)
Deferred compensation						110	(110)
Share-based compensation	$ 1	2,797							2,798
Share-based compensation (in shares)	29,575
Dividends and dividend equivalents					(12,321)				(12,321)
Shareholders' Equity Attributable to Parent, Ending Balance at Sep. 30, 2023	$ 686	360,453	(267,924)		1,598,875	12,617	(405,616)		1,299,091
Shares, Outstanding, Ending Balance at Sep. 30, 2023	45,625,771
Shareholders' Equity Attributable to Parent, Beginning Balance at Dec. 31, 2023	$ 686	362,345	(166,303)		1,609,785	13,539	(406,538)		1,413,514
Shares, Outstanding, Beginning Balance at Dec. 31, 2023	45,640,047
Increase Decrease In Shareholders Equity Roll Forward
Net Income (Loss)					127,900				127,900
Other comprehensive earnings (loss), net of tax			(12,671)						(12,671)
Deferred compensation						(790)	790
Share-based compensation	$ 1	4,356							4,357
Share-based compensation (in shares)	69,834
Dividends and dividend equivalents					(12,348)				(12,348)
Shareholders' Equity Attributable to Parent, Ending Balance at Mar. 31, 2024	$ 687	366,701	(178,974)		1,725,337	12,749	(405,748)		1,520,752
Shares, Outstanding, Ending Balance at Mar. 31, 2024	45,709,881
Shareholders' Equity Attributable to Parent, Beginning Balance at Dec. 31, 2023	$ 686	362,345	(166,303)		1,609,785	13,539	(406,538)		1,413,514
Shares, Outstanding, Beginning Balance at Dec. 31, 2023	45,640,047
Increase Decrease In Shareholders Equity Roll Forward
Net Income (Loss)									304,919
Other comprehensive earnings (loss), net of tax									59,779
Shareholders' Equity Attributable to Parent, Ending Balance at Sep. 30, 2024	$ 687	371,398	(106,524)		1,875,788	11,917	(404,916)		1,748,350
Shares, Outstanding, Ending Balance at Sep. 30, 2024	45,809,920
Shareholders' Equity Attributable to Parent, Beginning Balance at Mar. 31, 2024	$ 687	366,701	(178,974)		1,725,337	12,749	(405,748)		1,520,752
Shares, Outstanding, Beginning Balance at Mar. 31, 2024	45,709,881
Increase Decrease In Shareholders Equity Roll Forward
Net Income (Loss)					81,992				81,992
Other comprehensive earnings (loss), net of tax			(7,843)						(7,843)
Deferred compensation						434	(434)
Share-based compensation		3,084							3,084
Share-based compensation (in shares)	36,173
Dividends and dividend equivalents					(13,278)				(13,278)
Shareholders' Equity Attributable to Parent, Ending Balance at Jun. 30, 2024	$ 687	369,785	(186,817)		1,794,051	13,183	(406,182)		1,584,707
Shares, Outstanding, Ending Balance at Jun. 30, 2024	45,746,054
Increase Decrease In Shareholders Equity Roll Forward
Net Income (Loss)					95,027				95,027
Other comprehensive earnings (loss), net of tax			80,293						80,293
Deferred compensation						(1,266)	1,266
Share-based compensation		1,613							1,613
Share-based compensation (in shares)	63,866
Dividends and dividend equivalents					(13,290)				(13,290)
Shareholders' Equity Attributable to Parent, Ending Balance at Sep. 30, 2024	$ 687	$ 371,398	$ (106,524)		$ 1,875,788	$ 11,917	$ (404,916)		$ 1,748,350
Shares, Outstanding, Ending Balance at Sep. 30, 2024	45,809,920

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023
Statement Of Shareholders Equity [Abstract]
Cash dividends paid per common share	$ 0.29	$ 0.29	$ 0.27	$ 0.27	$ 0.27	$ 0.26

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Statement Of Cash Flows [Abstract]
Net cash provided by operating activities	$ 432,139	$ 342,192
Purchase of:
Fixed income securities, available-for-sale	(591,291)	(560,192)
Equity securities	(76,568)	(40,571)
Property and equipment	(4,187)	(5,451)
Other	(4,356)	(8,535)
Proceeds from sale of:
Fixed income securities - available-for-sale	80,245	26,158
Equity securities	44,863	36,708
Equity method investments		14,134
Other	4,624	550
Proceeds from call or maturity of:
Fixed income securities - available-for-sale	242,955	414,529
Net proceeds from sale (purchase) of short-term investments	(68,373)	(88,803)
Net cash used in investing activities	(372,088)	(211,473)
Cash Flows from Financing Activities
Proceeds from issuance of debt		50,000
Payment of debt		(150,000)
Cash dividends paid	(38,882)	(36,490)
Proceeds from stock option exercises	3,041	1,398
Net cash used in financing activities	(35,841)	(135,092)
Net increase (decrease) in cash	24,210	(4,373)
Cash at the beginning of the period	36,424	22,818
Cash at September 30	$ 60,634	$ 18,445

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	NOTES TO UNAUDITED CONDENSED CONSOLIDATED FINANCIAL STATEMENTS ​ 1. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES ​ A. BASIS OF PRESENTATION ​ The unaudited interim condensed consolidated financial statements of RLI Corp. (the Company) and subsidiaries have been prepared in accordance with generally accepted accounting principles in the United States of America (GAAP). These condensed consolidated financial statements do not include all the disclosures required by GAAP for annual financial statements and should be read in conjunction with our 2023 Annual Report on Form 10-K. In the opinion of the Company’s management, the condensed consolidated financial statements reflect all adjustments, of a normal and recurring nature, that are necessary for fair financial statement presentation. The results of operations for any interim period are not necessarily indicative of the operating results for a full year. ​ The preparation of the unaudited condensed consolidated financial statements requires management to make estimates and assumptions relating to the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of revenue and expenses during the period. These estimates are inherently subject to change and actual results could differ significantly from these estimates. ​ B. ADOPTED ACCOUNTING STANDARDS ​ No new accounting standards applicable in 2024 materially impact our financial statements. ​ C. PROSPECTIVE ACCOUNTING STANDARDS ​ 2023-07—Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures ​ The guidance in ASU 2023-07 was designed to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. This ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Although the Company continues to evaluate the impact of adopting this new accounting standard, the amendments are disclosure-related and should not have a material impact on our financial statements. ​ 2023-09—Income Taxes (Topic 740): Improvements to Income Tax Disclosures ​ The guidance in ASU 2023-09 was designed to increase transparency about income tax information through improvements to the rate reconciliation and disclosure of income taxes paid. This ASU is effective for fiscal years beginning after December 15, 2024. Although the Company continues to evaluate the impact of adopting this new accounting standard, the amendments are disclosure-related and should not have a material impact on our financial statements. ​ D. REINSURANCE ​ Ceded unearned premiums and reinsurance balances recoverable on unpaid losses and settlement expenses are reported separately as an asset, rather than being netted with the related liability, since reinsurance does not relieve the Company of our liability to policyholders. Such balances are subject to the credit risk associated with the individual reinsurer. We continually monitor the financial condition of our reinsurers and actively follow up on any past due or disputed amounts. As part of our monitoring efforts, we review reinsurers’ annual financial statements and Securities and Exchange Commission filings for those that are publicly traded. We also review insurance industry developments that may impact the financial condition of our reinsurers. We analyze the credit risk associated with our reinsurance balances recoverable by monitoring the AM Best and Standard & Poor’s (S&P) ratings of our reinsurers. We subject our reinsurance balances recoverable to detailed recoverability tests, including a segment-based analysis using the average default rating percentage by S&P rating, which assists the Company in assessing the sufficiency of its allowance. Additionally, we perform an in-depth reinsurer financial condition analysis prior to the renewal of our reinsurance placements. ​ Our policy is to charge to earnings, in the form of an allowance, an estimate of unrecoverable amounts from reinsurers. This allowance is reviewed on an ongoing basis to ensure that the amount makes a reasonable provision for reinsurance balances that we may be unable to recover. Once regulatory action (such as receivership, finding of insolvency, order of conservation or order of liquidation) is taken against a reinsurer, the paid and unpaid recoverable balances for the reinsurer are specifically identified and written off through the use of our allowance for estimated unrecoverable amounts from reinsurers. When we write-off such a balance, it is done in full. We then re-evaluate the overall allowance and determine whether the balance is sufficient and, if needed, an additional allowance is recognized. ​ The allowances for uncollectible amounts on paid and unpaid reinsurance balances recoverable were $16 million and $10 million, respectively, at September 30, 2024. At December 31, 2023, the amounts were $16 million and $11 million, respectively. Changes in the allowances were due to changes in the amount of reinsurance balances outstanding, the composition of reinsurers from whom the balances were recoverable and their associated S&P default ratings. No write-offs were applied to the allowances in the first nine months of 2024 and less than $1 million was recovered. ​ E. INTANGIBLE ASSETS ​ The composition of goodwill and intangible assets at September 30, 2024 and December 31, 2023 is detailed in the following table: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, (in thousands) 2024 2023 Goodwill ​ ​ ​ ​ ​ ​ Surety ​ $ 40,816 ​ $ 40,816 Casualty ​ ​ 5,246 ​ ​ 5,246 Total goodwill ​ $ 46,062 ​ $ 46,062 Indefinite-lived intangibles ​ ​ 7,500 ​ ​ 7,500 Total goodwill and intangibles ​ $ 53,562 ​ $ 53,562 ​ Annual impairment assessments were performed on our goodwill and state insurance license indefinite-lived intangible assets during the second quarter of 2024. Based upon these reviews, none of the assets were impaired. In addition, there were no triggering events as of September 30, 2024 that would suggest an updated impairment test would be needed for our goodwill and intangible assets. ​ F. EARNINGS PER SHARE ​ Basic earnings per share (EPS) is computed by dividing income available to common shareholders by the weighted-average number of common shares outstanding for the period. Diluted EPS reflects the dilution that could occur if securities or other contracts to issue common stock or common stock equivalents were exercised or converted into common stock. When inclusion of these items increases the earnings per share or reduces the loss per share, the effect on earnings is anti-dilutive. Under these circumstances, the diluted net earnings or net loss per share is computed excluding these items. The following represents a reconciliation of the numerator and denominator of the basic and diluted EPS computations contained in the unaudited condensed consolidated financial statements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months ​ For the Three Months ​ ​ Ended September 30, 2024 ​ Ended September 30, 2023 ​ ​ Income ​ Shares ​ Per Share ​ Income ​ Shares ​ Per Share (in thousands, except per share data) (Numerator) (Denominator) Amount (Numerator) (Denominator) Amount Basic EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 95,027 ​ 45,780 ​ $ 2.08 ​ $ 13,536 ​ 45,622 ​ $ 0.30 Effect of Dilutive Securities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ ​ — ​ 440 ​ ​ ​ ​ ​ — ​ 443 ​ ​ ​ Diluted EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 95,027 ​ 46,220 ​ $ 2.06 ​ $ 13,536 ​ 46,065 ​ $ 0.29 Anti-dilutive securities excluded from diluted EPS ​ ​ ​ ​ ​ 24 ​ ​ ​ ​ ​ ​ ​ ​ 145 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Nine Months ​ For the Nine Months ​ ​ Ended September 30, 2024 ​ Ended September 30, 2023 ​ ​ Income ​ Shares ​ Per Share ​ Income ​ Shares ​ Per Share (in thousands, except per share data) (Numerator) (Denominator) Amount (Numerator) (Denominator) Amount Basic EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 304,919 ​ 45,734 ​ $ 6.67 ​ $ 189,999 ​ 45,581 ​ $ 4.17 Effect of Dilutive Securities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ ​ — ​ 451 ​ ​ ​ ​ ​ — ​ 486 ​ ​ ​ Diluted EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 304,919 ​ 46,185 ​ $ 6.60 ​ $ 189,999 ​ 46,067 ​ $ 4.12 Anti-dilutive securities excluded from diluted EPS ​ ​ ​ ​ ​ 24 ​ ​ ​ ​ ​ ​ ​ ​ 145 ​ ​ ​ ​ G. COMPREHENSIVE EARNINGS ​ Our comprehensive earnings include net earnings plus after-tax unrealized gains and losses on our available-for-sale fixed income portfolio. In reporting the components of comprehensive earnings, we used the federal statutory tax rate of 21 percent. Other comprehensive earnings (loss), as shown in the consolidated statements of earnings and comprehensive earnings, is net of tax expense of $21 million for the third quarter of 2024, compared to $15 million of tax benefit for the same period in 2023. For the nine-month period ended September 30, 2024, other comprehensive earnings (loss) is net of tax expense of $16 million, compared to $10 million of tax benefit for the same period in 2023. ​ Unrealized gains, net of tax, recognized in other comprehensive earnings (loss) were $60 million for the first nine months of 2024, compared to $39 million of unrealized losses, net of tax, during the same period last year. The unrealized gains in 2024 were attributable to a decrease in interest rates, which increased the fair value of securities held in the fixed income portfolio. Interest rates increased during 2023, which decreased the fair value of securities held in the fixed income portfolio. ​ The following table illustrates the changes in the balance of each component of accumulated other comprehensive earnings (loss) for each period presented in the unaudited condensed consolidated financial statements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ For the Three Months ​ For the Nine Months ​ ​ Ended September 30, ​ Ended September 30, Unrealized Gains/Losses on Available-for-Sale Securities 2024 2023 2024 2023 Beginning balance ​ $ (186,817) ​ $ (211,090) ​ $ (166,303) ​ $ (229,076) Other comprehensive earnings (loss) before reclassifications ​ ​ 79,210 ​ ​ (57,261) ​ ​ 57,364 ​ ​ (41,355) Amounts reclassified from accumulated other comprehensive earnings ​ ​ 1,083 ​ ​ 427 ​ ​ 2,415 ​ ​ 2,507 Net current-period other comprehensive earnings (loss) ​ $ 80,293 ​ $ (56,834) ​ $ 59,779 ​ $ (38,848) Ending balance ​ $ (106,524) ​ $ (267,924) ​ $ (106,524) ​ $ (267,924) Balance of securities for which an allowance for credit losses has been recognized in net earnings ​ ​ ​ ​ ​ ​ ​ $ 1,813 ​ $ 2,005 ​ Credit losses on or the sale of an available-for-sale security results in amounts being reclassified from accumulated other comprehensive earnings (loss) to current period net earnings. The effects of reclassifications out of accumulated other comprehensive earnings (loss) by the respective line items of net earnings are presented in the following table: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amount Reclassified from Accumulated Other ​ ​ ​ (in thousands) ​ Comprehensive Earnings (Loss) ​ ​ ​ ​ ​ For the Three Months ​ For the Nine Months ​ ​ ​ Component of Accumulated ​ Ended September 30, ​ Ended September 30, ​ ​ Affected line item in the Other Comprehensive Earnings (Loss) 2024 2023 2024 2023 Statement of Earnings Unrealized gains and losses on available-for-sale securities ​ $ (1,365) ​ $ (271) ​ $ (3,129) ​ $ (2,808) ​ ​ Net realized gains (losses) ​ ​ ​ (6) ​ ​ (270) ​ ​ 72 ​ ​ (365) ​ ​ Credit gains (losses) presented within net realized gains ​ ​ $ (1,371) ​ $ (541) ​ $ (3,057) ​ $ (3,173) ​ ​ Earnings (loss) before income taxes ​ ​ ​ 288 ​ ​ 114 ​ ​ 642 ​ ​ 666 ​ ​ Income tax (expense) benefit ​ ​ $ (1,083) ​ $ (427) ​ $ (2,415) ​ $ (2,507) ​ ​ Net earnings (loss) ​ H. FAIR VALUE MEASUREMENTS ​ Fair value is defined as the price in the principal market that would be received for an asset to facilitate an orderly transaction between market participants on the measurement date. We determined the fair value of certain financial instruments based on their underlying characteristics and relevant transactions in the marketplace. We maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. ​ The following are the levels of the fair value hierarchy and a brief description of the type of valuation inputs that are used to establish each level. Financial assets are classified based upon the lowest level of significant input that is used to determine fair value. ​ Level 1 ​ Level 2 ​ Level 3 ​ As a part of management’s process to determine fair value, we utilize widely recognized, third-party pricing sources to determine our fair values. We have obtained an understanding of the third-party pricing sources’ valuation methodologies and inputs. The following is a description of the valuation techniques used for financial assets that are measured at fair value, including the general classification of such assets pursuant to the fair value hierarchy. ​ Corporate, Agencies, Government and Municipal Bonds: ​ Mortgage-backed Securities (MBS)/Commercial Mortgage-backed Securities (CMBS) and Asset-backed Securities (ABS): ​ Regulation D Private Placement Securities: observable and unobservable inputs. Observable inputs include public corporate spread matrices classified by sector, rating and average life, as well as investment and non-investment grade matrices created from fixed income indices. Unobservable inputs include a liquidity spread premium calculated based on public corporate spread and private corporate spread matrices. The quantitative detail of the liquidity spread premium is neither provided nor reasonably available to the Company. An increase to the credit spread assumptions would result in a lower fair value. ​ For all of our fixed income securities classified as Level 2, we periodically conduct a review to assess the reasonableness of the fair values provided by our pricing services. Our review consists of a two-pronged approach. First, we compare prices provided by our pricing services to those provided by an additional source. In some cases, we obtain prices from securities brokers and compare them to the prices provided by our pricing services. If discrepancies are found in our comparisons, we compare our prices to actual reported trade data for like securities. No changes to the fair values supplied by our pricing services have occurred as a result of our reviews. Based on these assessments, we have determined that the fair values of our Level 2 fixed income securities provided by our pricing services are reasonable. ​ Equity Securities: ​ Due to the relatively short-term nature of cash, short-term investments, accounts receivable and accounts payable, their carrying amounts are reasonable estimates of fair value. Our investments in private funds, classified as other invested assets, are measured using the investments’ net asset value per share and are not categorized within the fair value hierarchy. ​

Investments

Investments	9 Months Ended
	Sep. 30, 2024
Investments Debt And Equity Securities [Abstract]
Investments	2. INVESTMENTS ​ Our investments are primarily composed of fixed income debt securities and common stock equity securities. We carry our equity securities at fair value and categorize all of our debt securities as available-for-sale, which are carried at fair value. ​ Realized gains and losses on disposition of investments are based on the specific identification of the investments sold on the settlement date. The following is a summary of the disposition of fixed income and equity securities for the nine-month periods ended September 30, 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sales ​ Proceeds ​ Gross Realized ​ Net Realized (in thousands) From Sales Gains Losses Gain (Loss) 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed income securities - available-for-sale ​ $ 98,696 ​ $ 538 ​ $ (2,489) ​ $ (1,951) Equity securities ​ ​ 44,863 ​ ​ 20,276 ​ ​ (340) ​ ​ 19,936 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed income securities - available-for-sale ​ $ 25,983 ​ $ 145 ​ $ (1,035) ​ $ (890) Equity securities ​ ​ 36,708 ​ ​ 15,990 ​ ​ (101) ​ ​ 15,889 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Calls/Maturities ​ ​ ​ ​ Gross Realized ​ Net Realized (in thousands) Proceeds Gains Losses Gain (Loss) 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed income securities - available-for-sale ​ $ 240,200 ​ $ 89 ​ $ (1,062) ​ $ (973) 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed income securities - available-for-sale ​ $ 434,263 ​ $ 38 ​ $ (236) ​ $ (198) ​ FAIR VALUE MEASUREMENTS ​ Assets measured at fair value on a recurring basis as of September 30, 2024 and December 31, 2023 are summarized below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of September 30, 2024 ​ ​ Quoted Prices in ​ Significant Other ​ Significant ​ ​ ​ ​ ​ Active Markets for ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Identical Assets ​ Inputs ​ Inputs ​ ​ ​ (in thousands) (Level 1) (Level 2) (Level 3) Total Fixed income securities - available-for-sale ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government ​ $ — ​ $ 480,207 ​ $ — ​ $ 480,207 U.S. agency ​ ​ — ​ ​ 69,111 ​ ​ — ​ ​ 69,111 Non-U.S. government & agency ​ ​ — ​ ​ 7,261 ​ ​ — ​ ​ 7,261 Agency MBS ​ ​ — ​ ​ 420,390 ​ ​ — ​ ​ 420,390 ABS/CMBS/MBS* ​ ​ — ​ ​ 361,625 ​ ​ — ​ ​ 361,625 Corporate ​ ​ — ​ ​ 1,265,857 ​ ​ 86,836 ​ ​ 1,352,693 Municipal ​ ​ — ​ ​ 484,786 ​ ​ — ​ ​ 484,786 Total fixed income securities - available-for-sale ​ $ — ​ $ 3,089,237 ​ $ 86,836 ​ $ 3,176,073 Equity securities ​ ​ 725,047 ​ ​ — ​ ​ 4,691 ​ ​ 729,738 Total ​ $ 725,047 ​ $ 3,089,237 ​ $ 91,527 ​ $ 3,905,811 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2023 ​ ​ Quoted Prices in ​ Significant Other ​ Significant ​ ​ ​ ​ ​ Active Markets for ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Identical Assets ​ Inputs ​ Inputs ​ ​ ​ (in thousands) (Level 1) (Level 2) (Level 3) Total Fixed income securities - available-for-sale ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government ​ $ — ​ $ 308,031 ​ $ — ​ $ 308,031 U.S. agency ​ ​ — ​ ​ 59,826 ​ ​ — ​ ​ 59,826 Non-U.S. government & agency ​ ​ — ​ ​ 3,882 ​ ​ — ​ ​ 3,882 Agency MBS ​ ​ — ​ ​ 425,285 ​ ​ — ​ ​ 425,285 ABS/CMBS/MBS* ​ ​ — ​ ​ 281,182 ​ ​ — ​ ​ 281,182 Corporate ​ ​ — ​ ​ 1,164,548 ​ ​ 60,471 ​ ​ 1,225,019 Municipal ​ ​ — ​ ​ 552,624 ​ ​ — ​ ​ 552,624 Total fixed income securities - available-for-sale ​ $ — ​ $ 2,795,378 ​ $ 60,471 ​ $ 2,855,849 Equity securities ​ ​ 588,416 ​ ​ — ​ ​ 1,625 ​ ​ 590,041 Total ​ $ 588,416 ​ $ 2,795,378 ​ $ 62,096 ​ $ 3,445,890 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities ​ The following table summarizes changes in the balance of securities whose fair value was measured using significant unobservable inputs (Level 3). ​ ​ ​ ​ ​ (in thousands) Level 3 Securities Balance as of January 1, 2024 ​ $ 62,096 Net realized and unrealized gains (losses) ​ ​ ​ Included in other comprehensive earnings (loss) ​ ​ 2,789 Purchases ​ ​ 28,379 Sales / Calls / Maturities ​ ​ (1,737) Balance as of September 30, 2024 ​ $ 91,527 Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - included in other comprehensive earnings (loss) ​ $ 2,789 ​ The amortized cost and fair value of available-for-sale fixed income securities by contractual maturity as of September 30, 2024 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2024 (in thousands) Amortized Cost Fair Value Due in one year or less ​ $ 250,883 ​ $ 248,954 Due after one year through five years ​ ​ 797,980 ​ ​ 786,217 Due after five years through 10 years ​ ​ 880,694 ​ ​ 880,564 Due after 10 years ​ ​ 549,060 ​ ​ 478,323 ABS/CMBS/MBS* ​ ​ 824,067 ​ ​ 782,015 Total available-for-sale ​ $ 3,302,684 ​ $ 3,176,073 * Asset-backed, commercial mortgage-backed and mortgage-backed securities ​ The amortized cost and fair value of available-for-sale securities at September 30, 2024 and December 31, 2023 are presented in the tables below. Amortized cost does not include the $26 million and $23 million of accrued interest receivable as of September 30, 2024 and December 31, 2023, respectively. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2024 ​ ​ Cost or ​ Allowance ​ Gross ​ Gross ​ ​ ​ ​ ​ Amortized ​ for Credit ​ Unrealized ​ Unrealized ​ Fair (in thousands) Cost Losses Gains Losses Value U.S. government ​ $ 475,022 ​ $ — ​ $ 8,012 ​ $ (2,827) ​ $ 480,207 U.S. agency ​ ​ 68,861 ​ ​ — ​ ​ 1,177 ​ ​ (927) ​ ​ 69,111 Non-U.S. government & agency ​ ​ 7,958 ​ ​ — ​ ​ 62 ​ ​ (759) ​ ​ 7,261 Agency MBS ​ ​ 446,489 ​ ​ — ​ ​ 3,877 ​ ​ (29,976) ​ ​ 420,390 ABS/CMBS/MBS* ​ ​ 377,578 ​ ​ (26) ​ ​ 3,366 ​ ​ (19,293) ​ ​ 361,625 Corporate ​ ​ 1,372,681 ​ ​ (208) ​ ​ 15,936 ​ ​ (35,716) ​ ​ 1,352,693 Municipal ​ ​ 554,095 ​ ​ — ​ ​ 1,989 ​ ​ (71,298) ​ ​ 484,786 Total Fixed Income ​ $ 3,302,684 ​ $ (234) ​ $ 34,419 ​ $ (160,796) ​ $ 3,176,073 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 ​ ​ Cost or ​ Allowance ​ Gross ​ Gross ​ ​ ​ ​ ​ Amortized ​ for Credit ​ Unrealized ​ Unrealized ​ Fair (in thousands) Cost Losses Gains Losses Value U.S. government ​ $ 312,632 ​ $ — ​ $ 1,257 ​ $ (5,858) ​ $ 308,031 U.S. agency ​ ​ 60,763 ​ ​ — ​ ​ 652 ​ ​ (1,589) ​ ​ 59,826 Non-U.S. government & agency ​ ​ 4,800 ​ ​ — ​ ​ — ​ ​ (918) ​ ​ 3,882 Agency MBS ​ ​ 460,551 ​ ​ — ​ ​ 2,636 ​ ​ (37,902) ​ ​ 425,285 ABS/CMBS/MBS* ​ ​ 308,458 ​ ​ (3) ​ ​ 611 ​ ​ (27,884) ​ ​ 281,182 Corporate ​ ​ 1,273,187 ​ ​ (303) ​ ​ 8,766 ​ ​ (56,631) ​ ​ 1,225,019 Municipal ​ ​ 634,000 ​ ​ — ​ ​ 2,238 ​ ​ (83,614) ​ ​ 552,624 Total Fixed Income ​ $ 3,054,391 ​ $ (306) ​ $ 16,160 ​ $ (214,396) ​ $ 2,855,849 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities ​ Allowance for Credit Losses and Unrealized Losses on Fixed Income Securities ​ A reversable allowance for credit losses is recognized on available-for-sale fixed income securities. Several criteria are reviewed to determine if securities in the fixed income portfolio should be included in the allowance for expected credit loss evaluation, including: ​ ● Changes in technology that may impair the earnings potential of the investment, ​ ● The discontinuance of a segment of business that may affect future earnings potential, ​ ● Reduction of or non-payment of interest and/or principal, ​ ● Specific concerns related to the issuer’s industry or geographic area of operation, ​ ● Significant or recurring operating losses, poor cash flows and/or deteriorating liquidity ratios and ​ ● Downgrades in credit quality by a major rating agency. ​ If changes in interest rates and credit spreads do not reasonably explain the unrealized loss for an available-for-sale security, or if any of the criteria above indicate a potential credit loss, the security is subjected to a discounted cash flow analysis. Inputs into the discounted cash flow analysis include prepayment assumptions for structured securities, default rates and recoverability rates based on credit rating. The allowance for any security is limited to the amount that the security’s fair value is below amortized cost. As of September 30, 2024, the discounted cash flow analysis resulted in an allowance for credit losses on 11 securities. The following table presents changes in the allowance for expected credit losses on available-for-sale securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, ​ Nine Months Ended September 30, (in thousands) 2024 2023 2024 2023 Beginning balance ​ $ 228 ​ $ 434 ​ $ 306 ​ $ 339 Increase to allowance from securities for which credit losses were not previously recorded ​ ​ 30 ​ ​ 281 ​ ​ 30 ​ ​ 25 Reduction from securities sold during the period ​ ​ — ​ ​ — ​ ​ (89) ​ ​ — Net increase (decrease) from securities that had an allowance at the beginning of the period ​ ​ (24) ​ ​ (11) ​ ​ (13) ​ ​ 340 Balance as of September 30, ​ $ 234 ​ $ 704 ​ $ 234 ​ $ 704 ​ We recognized $2 million of losses on securities for which we no longer had the intent to hold until recovery during the first nine months of 2023. No such losses were recognized during the first nine months of 2024. ​ As of September 30, 2024, in addition to the securities included in the allowance for credit losses, the fixed income portfolio contained 1,134 securities with an unrealized loss position for which an allowance for credit losses had not been recorded. The $161 million in associated unrealized losses represents 5 percent of the fixed income portfolio’s cost basis and 4 percent of total invested assets. Isolated to these securities, unrealized losses decreased through the first nine months of 2024, as interest rates fell after the Federal Reserve cut rates in September. Of the total 1,134 securities, 1,045 have been in an unrealized loss position for 12 consecutive months or longer. The following table illustrates the total value of fixed income securities that were in an unrealized loss position as of September 30, 2024 and December 31, 2023 after factoring in the allowance for credit losses. All fixed income securities continue to pay the expected coupon payments and we believe we will recover the amortized cost basis of available-for-sale securities that remain in an unrealized loss position. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2024 ​ December 31, 2023 (in thousands) < 12 Mos. 12 Mos. & Greater Total < 12 Mos. 12 Mos. & Greater Total U.S. government ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ — ​ $ 174,088 ​ $ 174,088 ​ $ 37,718 ​ $ 204,556 ​ $ 242,274 Amortized cost ​ ​ — ​ ​ 176,915 ​ ​ 176,915 ​ ​ 37,950 ​ ​ 210,182 ​ ​ 248,132 Unrealized loss ​ $ — ​ $ (2,827) ​ $ (2,827) ​ $ (232) ​ $ (5,626) ​ $ (5,858) U.S. agency ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 3,707 ​ $ 29,421 ​ $ 33,128 ​ $ 8,736 ​ $ 29,632 ​ $ 38,368 Amortized cost ​ ​ 3,712 ​ ​ 30,343 ​ ​ 34,055 ​ ​ 8,790 ​ ​ 31,167 ​ ​ 39,957 Unrealized loss ​ $ (5) ​ $ (922) ​ $ (927) ​ $ (54) ​ $ (1,535) ​ $ (1,589) Non-U.S. government ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 1,391 ​ $ 4,044 ​ $ 5,435 ​ $ — ​ $ 3,882 ​ $ 3,882 Amortized cost ​ ​ 1,394 ​ ​ 4,800 ​ ​ 6,194 ​ ​ — ​ ​ 4,800 ​ ​ 4,800 Unrealized Loss ​ $ (3) ​ $ (756) ​ $ (759) ​ $ — ​ $ (918) ​ $ (918) Agency MBS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 18,667 ​ $ 250,519 ​ $ 269,186 ​ $ 61,196 ​ $ 275,707 ​ $ 336,903 Amortized cost ​ ​ 18,689 ​ ​ 280,473 ​ ​ 299,162 ​ ​ 61,714 ​ ​ 313,091 ​ ​ 374,805 Unrealized loss ​ $ (22) ​ $ (29,954) ​ $ (29,976) ​ $ (518) ​ $ (37,384) ​ $ (37,902) ABS/CMBS/MBS* ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 7,744 ​ $ 177,139 ​ $ 184,883 ​ $ 12,240 ​ $ 211,436 ​ $ 223,676 Amortized cost ​ ​ 7,757 ​ ​ 196,419 ​ ​ 204,176 ​ ​ 12,367 ​ ​ 239,193 ​ ​ 251,560 Unrealized loss ​ $ (13) ​ $ (19,280) ​ $ (19,293) ​ $ (127) ​ $ (27,757) ​ $ (27,884) Corporate ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 58,742 ​ $ 740,358 ​ $ 799,100 ​ $ 67,402 ​ $ 822,731 ​ $ 890,133 Amortized cost ​ ​ 59,635 ​ ​ 775,181 ​ ​ 834,816 ​ ​ 68,345 ​ ​ 878,419 ​ ​ 946,764 Unrealized loss ​ $ (893) ​ $ (34,823) ​ $ (35,716) ​ $ (943) ​ $ (55,688) ​ $ (56,631) Municipal ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 19,725 ​ $ 386,486 ​ $ 406,211 ​ $ 61,218 ​ $ 391,361 ​ $ 452,579 Amortized cost ​ ​ 19,850 ​ ​ 457,659 ​ ​ 477,509 ​ ​ 61,697 ​ ​ 474,496 ​ ​ 536,193 Unrealized loss ​ $ (125) ​ $ (71,173) ​ $ (71,298) ​ $ (479) ​ $ (83,135) ​ $ (83,614) Total fixed income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 109,976 ​ $ 1,762,055 ​ $ 1,872,031 ​ $ 248,510 ​ $ 1,939,305 ​ $ 2,187,815 Amortized cost ​ ​ 111,037 ​ ​ 1,921,790 ​ ​ 2,032,827 ​ ​ 250,863 ​ ​ 2,151,348 ​ ​ 2,402,211 Unrealized loss ​ $ (1,061) ​ $ (159,735) ​ $ (160,796) ​ $ (2,353) ​ $ (212,043) ​ $ (214,396) * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities ​ The following table shows the composition of the fixed income securities in unrealized loss positions, after factoring in the allowance for credit losses, at September 30, 2024 by the National Association of Insurance Commissioners (NAIC) rating and the generally equivalent Standard & Poor’s (S&P) and Moody’s ratings. The vast majority of the securities are rated by S&P and/or Moody’s. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Equivalent ​ Equivalent ​ (dollars in thousands) ​ ​ ​ NAIC S&P Moody’s ​ Amortized ​ ​ ​ ​ Unrealized ​ Percent ​ Rating Rating Rating Cost Fair Value Loss to Total ​ 1 ​ AAA/AA/A ​ Aaa/Aa/A ​ $ 1,660,081 ​ $ 1,517,662 ​ $ (142,419) ​ 88.6 % 2 ​ BBB ​ Baa ​ ​ 321,619 ​ ​ 305,816 ​ ​ (15,803) ​ 9.8 % 3 ​ BB ​ Ba ​ ​ 25,671 ​ ​ 24,974 ​ ​ (697) ​ 0.4 % 4 ​ B ​ B ​ ​ 21,703 ​ ​ 20,562 ​ ​ (1,141) ​ 0.7 % 5 ​ CCC ​ Caa ​ ​ 2,933 ​ ​ 2,610 ​ ​ (323) ​ 0.2 % 6 ​ CC or lower ​ Ca or lower ​ ​ 820 ​ ​ 407 ​ ​ (413) ​ 0.3 % ​ ​ ​ ​ Total ​ $ 2,032,827 ​ $ 1,872,031 ​ $ (160,796) ​ 100.0 % ​ Other Invested Assets ​ We had $54 million of other invested assets at September 30, 2024, compared to $59 million at December 31, 2023. Other invested assets include investments in low income housing tax credit partnerships (LIHTC) and historic tax credit partnerships (HTC), membership in the Federal Home Loan Bank of Chicago (FHLBC), and investments in private funds. Our LIHTC and HTC investments are carried at amortized cost and our investment in FHLBC stock is carried at cost. Due to the nature of the LIHTC, HTC and our membership in the FHLBC, their carrying amounts approximate fair value. The private funds are carried at fair value, using each investment’s net asset value. ​ Our LIHTC interests had a balance of $8 million at September 30, 2024, compared to $10 million on December 31, 2023. Our LIHTC interests recognized amortization of $1 million as a component of income tax expense and a total tax benefit of $1 million during the third quarter of 2024 and 2023. For the nine-months ended September 30, 2024, our LIHTC interests recognized amortization of $2 million and a total tax benefit of $2 million, compared to $2 million of amortization and $2 million of tax benefit for the same period in 2023. Our unfunded commitment for our LIHTC investments was less than $1 million at September 30, 2024 and will be paid out in installments through 2035. ​ Our HTC investment had a balance of $9 million at September 30, 2024, compared to $13 million at December 31, 2023. Our HTC investment recognized $1 million of amortization as a component of income tax expense and a total tax benefit of $2 million during the third quarter of 2024, compared to $1 million of amortization and $1 million of tax benefit for the same period in 2023. For the nine-months ended September 30, 2024 and 2023, our HTC investment recognized amortization of $3 million and a total tax benefit of $4 million. ​ As of September 30, 2024, $57 million of investments ​ Our investments in private funds totaled $25 million as of September 30, 2024, down from $28 million as of December 31, 2023, and had $4 million of associated unfunded commitments at September 30, 2024. Our interest in private funds is generally restricted from being transferred or otherwise redeemed without prior consent by the respective entities, and the timed dissolution of the partnerships would trigger redemption. ​ Investments in Unconsolidated Investees ​ We had $65 million of investments in unconsolidated investees at September 30, 2024, compared to $57 million at December 31, 2023. At September 30, 2024, our investment in Prime Holdings Insurance Services, Inc. (Prime) was $65 million and other investments in unconsolidated investees totaled less than $1 million. We received dividends of $3 million from Prime in 2024, while no dividends were received from Prime in 2023. ​ Cash and Short-Term Investments ​ Cash consists of uninvested balances in bank accounts. Short-term investments consist of investments with original maturities of 90 days or less, primarily AAA-rated government money market funds. Short-term investments are carried at cost. We had a cash and short-term investment balance of $61 million and $203 million, respectively, at September 30, 2024, compared to $36 million and $135 million, respectively, at December 31, 2023.

Historical Loss And LAE Develop

Historical Loss And LAE Development	9 Months Ended
	Sep. 30, 2024
Historical Loss And L A E Development Disclosure [Abstract]
Historical Loss And LAE Development	3. HISTORICAL LOSS AND LAE DEVELOPMENT ​ The following table is a reconciliation of our unpaid losses and settlement expenses (LAE) for the first nine months of 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Nine Months ​ ​ Ended September 30, (in thousands) 2024 2023 Unpaid losses and LAE at beginning of year ​ ​ ​ ​ ​ ​ Gross ​ $ 2,446,025 ​ $ 2,315,637 Ceded ​ ​ (757,349) ​ ​ (740,089) Net ​ $ 1,688,676 ​ $ 1,575,548 ​ ​ ​ ​ ​ ​ ​ Increase (decrease) in incurred losses and LAE ​ ​ ​ ​ ​ ​ Current accident year ​ $ 599,183 ​ $ 551,975 Prior accident years ​ ​ (85,442) ​ ​ (93,986) Total incurred ​ $ 513,741 ​ $ 457,989 ​ ​ ​ ​ ​ ​ ​ Loss and LAE payments for claims incurred ​ ​ ​ ​ ​ ​ Current accident year ​ $ (76,148) ​ $ (113,010) Prior accident years ​ ​ (273,868) ​ ​ (252,786) Total paid ​ $ (350,016) ​ $ (365,796) ​ ​ ​ ​ ​ ​ ​ Net unpaid losses and LAE at September 30, ​ $ 1,852,401 ​ $ 1,667,741 ​ ​ ​ ​ ​ ​ ​ Unpaid losses and LAE at September 30, ​ ​ ​ ​ ​ ​ Gross ​ $ 2,611,941 ​ $ 2,488,695 Ceded ​ ​ (759,540) ​ ​ (820,954) Net ​ $ 1,852,401 ​ $ 1,667,741 ​ For the first nine months of 2024, incurred losses and LAE included $85 million of favorable development on prior years’ loss reserves, largely from accident years 2016, 2017, 2019, 2020, 2022 and 2023. Marine, surety, commercial property, commercial excess, general liability, professional services, executive products and personal umbrella were drivers of the favorable development. No products experienced significant adverse development. ​ For the first nine months of 2023, incurred losses and LAE included $94 million of favorable development on prior years’ loss reserves, largely from accident years 2016 through 2018 and 2020 through 2022. Commercial excess, executive products, general liability, professional services, personal umbrella, surety and commercial property were drivers of the favorable development. No products experienced significant adverse development.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2024
Income Tax Disclosure
Income Taxes	4. INCOME TAXES ​ Our effective tax rate for the three and nine months ended September 30, 2024 was 18.7 percent and 19.8 percent, respectively, compared to 9.9 percent and 18.7 percent, respectively, for the same periods in 2023. Effective rates are dependent upon components of pretax earnings and the related tax effects. The effective tax rate was higher for the three and nine-month periods in 2024 due to higher levels of pretax income, which decreased the percentage impact of tax-favored adjustments. ​ Income tax expense attributable to income from operations for the three and nine-month periods ended September 30, 2024 and 2023 differed from the amounts computed by applying the U.S. federal tax rate of 21 percent to pretax income by the items detailed in the table below. In interim periods, income taxes are adjusted to reflect the effective tax rate we anticipate for the year, with adjustments flowing through the other items, net line. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months Ended September 30, ​ For the Nine Months Ended September 30, 2024 ​ ​ ​ 2024 ​ 2023 ​ 2024 ​ 2023 ​ (in thousands) Amount % Amount % Amount % Amount % ​ Provision for income taxes at the statutory rate of 21% ​ $ 24,533 ​ 21.0 % $ 3,154 ​ 21.0 % $ 79,825 ​ 21.0 % $ 49,107 ​ 21.0 % Increase (reduction) in taxes resulting from: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Excess tax benefit on share-based compensation ​ ​ (1,967) ​ (1.7) % ​ (395) ​ (2.6) % ​ (4,264) ​ (1.1) % ​ (3,263) ​ (1.4) % Tax exempt interest income ​ ​ (216) ​ (0.2) % ​ (270) ​ (1.8) % ​ (725) ​ (0.2) % ​ (827) ​ (0.4) % Dividends received deduction ​ ​ (588) ​ (0.5) % ​ (164) ​ (1.1) % ​ (1,056) ​ (0.3) % ​ (597) ​ (0.3) % Tax credit ​ ​ (1,093) ​ (0.9) % ​ (779) ​ (5.2) % ​ (2,629) ​ (0.7) % ​ (2,338) ​ (1.0) % ESOP dividends paid deduction ​ ​ (149) ​ (0.1) % ​ (142) ​ (1.0) % ​ (439) ​ (0.1) % ​ (423) ​ (0.2) % Nondeductible expenses ​ ​ 1,160 ​ 1.0 % ​ 158 ​ 1.1 % ​ 2,819 ​ 0.7 % ​ 1,505 ​ 0.6 % Other items, net ​ ​ 118 ​ 0.1 % ​ (79) ​ (0.5) % ​ 1,669 ​ 0.5 % ​ 678 ​ 0.4 % Total tax expense ​ $ 21,798 ​ 18.7 % $ 1,483 ​ 9.9 % $ 75,200 ​ 19.8 % $ 43,842 ​ 18.7 % ​ We have recorded our deferred tax assets and liabilities using the statutory federal tax rate of 21 percent. We believe it is more likely than not that all deferred tax assets will be recovered, given the carry back availability as well as the result of future operations, which we believe will generate sufficient taxable income to realize the deferred tax asset.

Stock Based Compensation

Stock Based Compensation	9 Months Ended
	Sep. 30, 2024
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Based Compensation	5. STOCK BASED COMPENSATION ​ Our RLI Corp. Long-Term Incentive Plan (2015 LTIP) was in place from 2015 to 2023. The 2015 LTIP provided for equity-based compensation, including stock options and restricted stock units, up to a maximum of 4,000,000 shares of common stock (subject to adjustment for changes in our capitalization and other events). Between 2015 and 2023, we granted 3,291,388 awards under the 2015 LTIP. The 2015 LTIP was replaced in 2023. ​ In 2023, our shareholders approved the 2023 RLI Corp. Long-Term Incentive Plan (2023, LTIP), which provides for equity-based compensation. In conjunction with the adoption of the 2023 LTIP, effective May 4, 2023, awards are no longer granted under the 2015 LTIP. Awards under the 2023 LTIP may be in the form of restricted stock, restricted stock units, stock options (incentive or non-qualified), stock appreciation rights, performance units as well as other stock-based awards. Eligibility under the 2023 LTIP is limited to employees, directors, consultants and independent contractors of the Company or any affiliate. The granting of awards under the 2023 LTIP is solely at the discretion of the Human Capital and Compensation Committee of the board of directors or its delegate. The maximum number of shares of common stock available for distribution under the 2023 LTIP is 4,004,891 shares (subject to adjustment for changes in our capitalization and other events). Since the plan’s approval in 2023, we have granted 382,021 awards under the 2023 LTIP, including 186,483 thus far in 2024. ​ Compensation expense is based on the probable number of awards expected to vest. The total compensation expense related to equity awards was $2 million and $6 million in the three and nine-month periods ended September 30, 2024, respectively, compared to $2 million and $7 million, respectively, for the same periods in 2023. The total income tax benefit was less than $1 million and $1 million for the three and nine-month periods ended September 30, 2024 and 2023. Total unrecognized compensation expense relating to outstanding and unvested awards was $8 million, which will be recognized over the weighted average vesting period of 2.64 years. ​ Stock Options ​ Under the 2023 LTIP, as under the 2015 LTIP, we grant stock options for shares with an exercise price equal to the fair market value of the shares at the date of grant (subject to adjustments for changes in our capitalization, special dividends and other events as set forth in such plans). Options generally vest and become exercisable over a five-year period and expire eight years after grant. ​ For most participants, the requisite service period and vesting period will be the same. For participants who are retirement eligible, defined by the plan as those individuals whose age and years of service equals 75 or greater, the requisite service period is deemed to be met and options are immediately expensed on the date of grant. For participants who will become retirement eligible during the vesting period, the requisite service period over which expense is recognized is the period between the grant date and the attainment of retirement eligibility. Shares issued upon option exercise are newly issued shares. ​ The following tables summarize option activity for the nine-month period ended September 30, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Aggregate ​ ​ ​ ​ Weighted ​ Average ​ Intrinsic ​ ​ ​ ​ Average ​ Remaining ​ Value ​ Options Exercise Price Contractual Life (in 000’s) Outstanding options at January 1, 2024 ​ 1,641,710 ​ $ 92.62 ​ ​ ​ ​ ​ Options granted ​ 165,802 ​ ​ 142.78 ​ ​ ​ ​ ​ Options exercised ​ (237,765) ​ ​ 66.39 ​ ​ ​ ​ ​ Options canceled/forfeited ​ (8,900) ​ ​ 113.28 ​ ​ ​ ​ ​ Outstanding options at September 30, 2024 ​ 1,560,847 ​ $ 101.82 ​ 4.48 ​ $ 82,970 Exercisable options at September 30, 2024 ​ 920,068 ​ $ 88.05 ​ 3.35 ​ $ 61,578 ​ The intrinsic value of options exercised, which is the difference between the fair value and the exercise price, was $19 million and $17 million during the first nine months of 2024 and 2023, respectively. ​ The fair value of options was estimated using a Black-Scholes based option pricing model with the following weighted average grant-date assumptions and weighted average fair values as of September 30: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 ​ Weighted-average fair value of grants ​ $ 31.29 ​ $ 26.71 ​ Risk-free interest rates ​ ​ 4.92 % ​ 3.41 % Dividend yield ​ ​ 2.30 % ​ 2.29 % Expected volatility ​ ​ 23.08 % ​ 22.96 % Expected option life ​ ​ 5.00 years ​ 4.94 years ​ The risk-free rate was determined based on U.S. treasury yields that most closely approximated the options’ expected life. The dividend yield was determined based on the average annualized quarterly dividends paid during the most recent five-year period and incorporated a consideration for special dividends paid in recent history. The expected volatility was calculated based on the median of the rolling volatilities for the expected life of the options. The expected option life was determined based on historical exercise behavior and the assumption that all outstanding options will be exercised at the midpoint of the current date and remaining contractual term, adjusted for the demographics of the current year’s grant. ​ Restricted Stock Units ​ In addition to stock options, restricted stock units (RSUs) are granted with a value equal to the closing stock price of the Company’s stock on the dates the units are granted. For employees, these units generally have a three-year cliff vesting, but have an accelerated vesting feature for participants who are retirement eligible, defined by the plan as those individuals whose age and years of service equals 75 or greater. For directors, these units vest on the earlier of one year from the date of grant or the next annual shareholders meeting. In addition, the RSUs have dividend participation, which accrue as additional units and are settled with granted stock units at the end of the vesting period. The total fair value of restricted stock units that vested was $2 million and $3 million during the first nine months of 2024 and 2023, respectively. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ ​ ​ Grant Date ​ RSUs Fair Value Nonvested at January 1, 2024 ​ 45,093 ​ $ 125.16 Granted ​ 20,681 ​ ​ 143.43 Reinvested ​ 269 ​ ​ 146.77 Vested ​ (17,198) ​ ​ 122.96 Forfeited ​ (1,181) ​ ​ 134.00 Nonvested at September 30, 2024 ​ 47,664 ​ $ 133.79 ​

Operating Segment Information

Operating Segment Information	9 Months Ended
	Sep. 30, 2024
Segment Reporting [Abstract]
Operating Segment Information	6. OPERATING SEGMENT INFORMATION Selected information by operating segment is presented in the table below. Additionally, the table reconciles segment totals to total earnings and total revenues. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months ​ For the Nine Months Revenues ​ Ended September 30, ​ Ended September 30, (in thousands) 2024 2023 2024 2023 Casualty ​ $ 219,638 ​ $ 189,305 ​ $ 627,014 ​ $ 562,384 Property ​ ​ 133,266 ​ ​ 94,988 ​ ​ 396,774 ​ ​ 285,596 Surety ​ ​ 36,585 ​ ​ 34,116 ​ ​ 105,442 ​ ​ 100,432 Net premiums earned ​ $ 389,489 ​ $ 318,409 ​ $ 1,129,230 ​ $ 948,412 Net investment income ​ ​ 36,694 ​ ​ 31,963 ​ ​ 103,502 ​ ​ 87,835 Net realized gains ​ ​ 5,420 ​ ​ 6,558 ​ ​ 11,222 ​ ​ 26,758 Net unrealized gains (losses) on equity securities ​ ​ 38,392 ​ ​ (25,236) ​ ​ 87,314 ​ ​ 15,474 Total consolidated revenue ​ $ 469,995 ​ $ 331,694 ​ $ 1,331,268 ​ $ 1,078,479 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net Earnings ​ ​ ​ ​ ​ ​ (in thousands) 2024 2023 2024 2023 Casualty ​ $ 2,549 ​ $ 18,670 ​ $ 26,538 ​ $ 57,478 Property ​ ​ 30,402 ​ ​ (20,671) ​ ​ 141,298 ​ ​ 33,589 Surety ​ ​ 7,741 ​ ​ 6,248 ​ ​ 20,575 ​ ​ 22,271 Net underwriting income ​ $ 40,692 ​ $ 4,247 ​ $ 188,411 ​ $ 113,338 Net investment income ​ ​ 36,694 ​ ​ 31,963 ​ ​ 103,502 ​ ​ 87,835 Net realized gains ​ ​ 5,420 ​ ​ 6,558 ​ ​ 11,222 ​ ​ 26,758 Net unrealized gains (losses) on equity securities ​ ​ 38,392 ​ ​ (25,236) ​ ​ 87,314 ​ ​ 15,474 General corporate expense and interest on debt ​ ​ (5,611) ​ ​ (4,245) ​ ​ (17,983) ​ ​ (16,733) Equity in earnings of unconsolidated investees ​ ​ 1,238 ​ ​ 1,732 ​ ​ 7,653 ​ ​ 7,169 Earnings before income taxes ​ $ 116,825 ​ $ 15,019 ​ $ 380,119 ​ $ 233,841 Income tax expense ​ ​ 21,798 ​ ​ 1,483 ​ ​ 75,200 ​ ​ 43,842 Net earnings ​ $ 95,027 ​ $ 13,536 ​ $ 304,919 ​ $ 189,999 ​ The following table further summarizes revenues by major product type within each operating segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months ​ For the Nine Months Net Premiums Earned ​ Ended September 30, ​ Ended September 30, (in thousands) 2024 2023 2024 2023 Casualty ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial excess and personal umbrella ​ $ 91,434 ​ $ 72,559 ​ $ 257,455 ​ $ 209,402 Commercial transportation ​ ​ 32,067 ​ ​ 25,843 ​ ​ 88,691 ​ ​ 76,473 General liability ​ ​ 26,316 ​ ​ 25,250 ​ ​ 77,832 ​ ​ 77,166 Professional services ​ ​ 26,281 ​ ​ 24,882 ​ ​ 77,366 ​ ​ 73,841 Small commercial ​ ​ 20,074 ​ ​ 18,096 ​ ​ 57,870 ​ ​ 54,492 Executive products ​ ​ 6,261 ​ ​ 5,943 ​ ​ 17,624 ​ ​ 18,449 Other casualty ​ ​ 17,205 ​ ​ 16,732 ​ ​ 50,176 ​ ​ 52,561 Total ​ $ 219,638 ​ $ 189,305 ​ $ 627,014 ​ $ 562,384 Property ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial property ​ $ 85,814 ​ $ 63,783 ​ $ 260,819 ​ $ 173,264 Marine ​ ​ 37,618 ​ ​ 33,436 ​ ​ 107,255 ​ ​ 96,484 Other property ​ ​ 9,834 ​ ​ (2,231) ​ ​ 28,700 ​ ​ 15,848 Total ​ $ 133,266 ​ $ 94,988 ​ $ 396,774 ​ $ 285,596 Surety ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Transactional ​ $ 12,488 ​ $ 11,966 ​ $ 36,904 ​ $ 35,900 Commercial ​ ​ 12,477 ​ ​ 12,653 ​ ​ 35,802 ​ ​ 37,576 Contract ​ ​ 11,620 ​ ​ 9,497 ​ ​ 32,736 ​ ​ 26,956 Total ​ $ 36,585 ​ $ 34,116 ​ $ 105,442 ​ $ 100,432 Grand Total ​ $ 389,489 ​ $ 318,409 ​ $ 1,129,230 ​ $ 948,412 ​

Leases

Leases	9 Months Ended
	Sep. 30, 2024
Leases [Abstract]
Leases	7. LEASES ​ Right-of-use (ROU) assets are included in the other assets line item and lease liabilities are included in the other liabilities line item of the consolidated balance sheet. We determine if a contract contains a lease at inception and recognize operating lease ROU assets and operating lease liabilities based on the present value of the future minimum lease payments at the commencement date. As our leases do not provide an implicit rate, we use our incremental borrowing rate based on the information available at the commencement date in determining the present value of future payments. Lease agreements may include options to extend or terminate. The options are exercised at our discretion and are included in operating lease liabilities if it is reasonably certain the option will be exercised. Lease agreements have lease and non-lease components, which are accounted for as a single lease component. Operating lease costs for future minimum lease payments are recognized on a straight-line basis over the lease terms. Variable lease costs are expensed in the period in which the obligations are incurred. Sublease income is recognized on a straight-line basis over the sublease term. ​ The Company’s operating lease obligations are for branch office facilities. The components of lease expense and other lease information as of and during the three and nine-month periods ended September 30, 2024 and 2023 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months ​ For the Nine Months ​ ​ Ended September 30, ​ Ended September 30, (in thousands) 2024 2023 2024 2023 Operating lease cost ​ $ 1,149 ​ $ 1,235 ​ $ 3,483 ​ $ 3,743 Variable lease cost ​ ​ 351 ​ ​ 320 ​ ​ 966 ​ ​ 1,202 Sublease income ​ ​ (42) ​ ​ (139) ​ ​ (127) ​ ​ (416) Total lease cost ​ $ 1,458 ​ $ 1,416 ​ $ 4,322 ​ $ 4,529 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash paid for amounts included in measurement of lease liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash outflows from operating leases ​ $ 845 ​ $ 1,431 ​ $ 3,013 ​ $ 4,186 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ROU assets obtained in exchange for new operating lease liabilities ​ $ 351 ​ $ 319 ​ $ 4,140 ​ $ 1,303 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Reduction to ROU assets resulting from reduction to lease liabilities ​ $ — ​ $ — ​ $ — ​ $ 200 ​ ​ ​ ​ ​ ​ ​ ​ ​ (in thousands) September 30, 2024 December 31, 2023 ​ Operating lease ROU assets ​ $ 14,768 ​ $ 13,666 ​ Operating lease liabilities ​ $ 16,384 ​ $ 14,880 ​ Weighted-average remaining lease term - operating leases ​ ​ 6.04 years ​ 6.08 years Weighted-average discount rate - operating leases ​ ​ 3.59 % ​ 3.21 % ​ Future minimum lease payments under non-cancellable leases as of September 30, 2024 were as follows: ​ ​ ​ ​ ​ (in thousands) September 30, 2024 2024 ​ $ 1,070 2025 ​ ​ 4,339 2026 ​ ​ 3,633 2027 ​ ​ 2,207 2028 ​ ​ 1,537 2029 ​ ​ 1,443 Thereafter ​ ​ 4,489 Total future minimum lease payments ​ $ 18,718 Less imputed interest ​ ​ (2,334) Total operating lease liability ​ $ 16,384 ​

Acquisitions and Dispositions

Acquisitions and Dispositions	9 Months Ended
	Sep. 30, 2024
Business Combination and Asset Acquisition [Abstract]
Acquisitions and Dispositions	8. ACQUISITONS AND DISPOSTIONS ​ On September 30, 2022, RLI Corp. completed the sale of its equity method investment in Maui Jim, Inc. to Kering Eyewear. During the first quarter of 2023, the payout of the working capital escrow resulted in the recognition of a $14 million gain that was recorded in the net realized gain line item of the statement of earnings.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2024
Subsequent Events [Abstract]
Subsequent Events	9. Subsequent Events ​ In early October 2024, Hurricane Milton made landfall in Florida as a Category 3 storm. We currently estimate that losses for Hurricane Milton, net of any reinsurance benefits, will be between $45 million and $55 million. Our estimates are subject to change and losses from the event will be reflected in our fourth quarter 2024 results.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ 95,027	$ 81,992	$ 127,900	$ 13,536	$ 77,652	$ 98,811	$ 304,919	$ 189,999

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Sep. 30, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Basis of Presentation and Sum_2

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	A. BASIS OF PRESENTATION ​ The unaudited interim condensed consolidated financial statements of RLI Corp. (the Company) and subsidiaries have been prepared in accordance with generally accepted accounting principles in the United States of America (GAAP). These condensed consolidated financial statements do not include all the disclosures required by GAAP for annual financial statements and should be read in conjunction with our 2023 Annual Report on Form 10-K. In the opinion of the Company’s management, the condensed consolidated financial statements reflect all adjustments, of a normal and recurring nature, that are necessary for fair financial statement presentation. The results of operations for any interim period are not necessarily indicative of the operating results for a full year. ​ The preparation of the unaudited condensed consolidated financial statements requires management to make estimates and assumptions relating to the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of revenue and expenses during the period. These estimates are inherently subject to change and actual results could differ significantly from these estimates.
Adopted Accounting Standards	B. ADOPTED ACCOUNTING STANDARDS ​ No new accounting standards applicable in 2024 materially impact our financial statements.
Prospective Accounting Standards	​ C. PROSPECTIVE ACCOUNTING STANDARDS ​ 2023-07—Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures ​ The guidance in ASU 2023-07 was designed to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. This ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Although the Company continues to evaluate the impact of adopting this new accounting standard, the amendments are disclosure-related and should not have a material impact on our financial statements. ​ 2023-09—Income Taxes (Topic 740): Improvements to Income Tax Disclosures ​ The guidance in ASU 2023-09 was designed to increase transparency about income tax information through improvements to the rate reconciliation and disclosure of income taxes paid. This ASU is effective for fiscal years beginning after December 15, 2024. Although the Company continues to evaluate the impact of adopting this new accounting standard, the amendments are disclosure-related and should not have a material impact on our financial statements.
Reinsurance	​ D. REINSURANCE ​ Ceded unearned premiums and reinsurance balances recoverable on unpaid losses and settlement expenses are reported separately as an asset, rather than being netted with the related liability, since reinsurance does not relieve the Company of our liability to policyholders. Such balances are subject to the credit risk associated with the individual reinsurer. We continually monitor the financial condition of our reinsurers and actively follow up on any past due or disputed amounts. As part of our monitoring efforts, we review reinsurers’ annual financial statements and Securities and Exchange Commission filings for those that are publicly traded. We also review insurance industry developments that may impact the financial condition of our reinsurers. We analyze the credit risk associated with our reinsurance balances recoverable by monitoring the AM Best and Standard & Poor’s (S&P) ratings of our reinsurers. We subject our reinsurance balances recoverable to detailed recoverability tests, including a segment-based analysis using the average default rating percentage by S&P rating, which assists the Company in assessing the sufficiency of its allowance. Additionally, we perform an in-depth reinsurer financial condition analysis prior to the renewal of our reinsurance placements. ​ Our policy is to charge to earnings, in the form of an allowance, an estimate of unrecoverable amounts from reinsurers. This allowance is reviewed on an ongoing basis to ensure that the amount makes a reasonable provision for reinsurance balances that we may be unable to recover. Once regulatory action (such as receivership, finding of insolvency, order of conservation or order of liquidation) is taken against a reinsurer, the paid and unpaid recoverable balances for the reinsurer are specifically identified and written off through the use of our allowance for estimated unrecoverable amounts from reinsurers. When we write-off such a balance, it is done in full. We then re-evaluate the overall allowance and determine whether the balance is sufficient and, if needed, an additional allowance is recognized. ​ The allowances for uncollectible amounts on paid and unpaid reinsurance balances recoverable were $16 million and $10 million, respectively, at September 30, 2024. At December 31, 2023, the amounts were $16 million and $11 million, respectively. Changes in the allowances were due to changes in the amount of reinsurance balances outstanding, the composition of reinsurers from whom the balances were recoverable and their associated S&P default ratings. No write-offs were applied to the allowances in the first nine months of 2024 and less than $1 million was recovered. ​
Intangible Assets	E. INTANGIBLE ASSETS ​ The composition of goodwill and intangible assets at September 30, 2024 and December 31, 2023 is detailed in the following table: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, (in thousands) 2024 2023 Goodwill ​ ​ ​ ​ ​ ​ Surety ​ $ 40,816 ​ $ 40,816 Casualty ​ ​ 5,246 ​ ​ 5,246 Total goodwill ​ $ 46,062 ​ $ 46,062 Indefinite-lived intangibles ​ ​ 7,500 ​ ​ 7,500 Total goodwill and intangibles ​ $ 53,562 ​ $ 53,562 ​ Annual impairment assessments were performed on our goodwill and state insurance license indefinite-lived intangible assets during the second quarter of 2024. Based upon these reviews, none of the assets were impaired. In addition, there were no triggering events as of September 30, 2024 that would suggest an updated impairment test would be needed for our goodwill and intangible assets.
Earnings Per Share	F. EARNINGS PER SHARE ​ Basic earnings per share (EPS) is computed by dividing income available to common shareholders by the weighted-average number of common shares outstanding for the period. Diluted EPS reflects the dilution that could occur if securities or other contracts to issue common stock or common stock equivalents were exercised or converted into common stock. When inclusion of these items increases the earnings per share or reduces the loss per share, the effect on earnings is anti-dilutive. Under these circumstances, the diluted net earnings or net loss per share is computed excluding these items. The following represents a reconciliation of the numerator and denominator of the basic and diluted EPS computations contained in the unaudited condensed consolidated financial statements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months ​ For the Three Months ​ ​ Ended September 30, 2024 ​ Ended September 30, 2023 ​ ​ Income ​ Shares ​ Per Share ​ Income ​ Shares ​ Per Share (in thousands, except per share data) (Numerator) (Denominator) Amount (Numerator) (Denominator) Amount Basic EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 95,027 ​ 45,780 ​ $ 2.08 ​ $ 13,536 ​ 45,622 ​ $ 0.30 Effect of Dilutive Securities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ ​ — ​ 440 ​ ​ ​ ​ ​ — ​ 443 ​ ​ ​ Diluted EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 95,027 ​ 46,220 ​ $ 2.06 ​ $ 13,536 ​ 46,065 ​ $ 0.29 Anti-dilutive securities excluded from diluted EPS ​ ​ ​ ​ ​ 24 ​ ​ ​ ​ ​ ​ ​ ​ 145 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Nine Months ​ For the Nine Months ​ ​ Ended September 30, 2024 ​ Ended September 30, 2023 ​ ​ Income ​ Shares ​ Per Share ​ Income ​ Shares ​ Per Share (in thousands, except per share data) (Numerator) (Denominator) Amount (Numerator) (Denominator) Amount Basic EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 304,919 ​ 45,734 ​ $ 6.67 ​ $ 189,999 ​ 45,581 ​ $ 4.17 Effect of Dilutive Securities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ ​ — ​ 451 ​ ​ ​ ​ ​ — ​ 486 ​ ​ ​ Diluted EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 304,919 ​ 46,185 ​ $ 6.60 ​ $ 189,999 ​ 46,067 ​ $ 4.12 Anti-dilutive securities excluded from diluted EPS ​ ​ ​ ​ ​ 24 ​ ​ ​ ​ ​ ​ ​ ​ 145 ​ ​ ​ ​
Comprehensive Earnings	G. COMPREHENSIVE EARNINGS ​ Our comprehensive earnings include net earnings plus after-tax unrealized gains and losses on our available-for-sale fixed income portfolio. In reporting the components of comprehensive earnings, we used the federal statutory tax rate of 21 percent. Other comprehensive earnings (loss), as shown in the consolidated statements of earnings and comprehensive earnings, is net of tax expense of $21 million for the third quarter of 2024, compared to $15 million of tax benefit for the same period in 2023. For the nine-month period ended September 30, 2024, other comprehensive earnings (loss) is net of tax expense of $16 million, compared to $10 million of tax benefit for the same period in 2023. ​ Unrealized gains, net of tax, recognized in other comprehensive earnings (loss) were $60 million for the first nine months of 2024, compared to $39 million of unrealized losses, net of tax, during the same period last year. The unrealized gains in 2024 were attributable to a decrease in interest rates, which increased the fair value of securities held in the fixed income portfolio. Interest rates increased during 2023, which decreased the fair value of securities held in the fixed income portfolio. ​ The following table illustrates the changes in the balance of each component of accumulated other comprehensive earnings (loss) for each period presented in the unaudited condensed consolidated financial statements: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ For the Three Months ​ For the Nine Months ​ ​ Ended September 30, ​ Ended September 30, Unrealized Gains/Losses on Available-for-Sale Securities 2024 2023 2024 2023 Beginning balance ​ $ (186,817) ​ $ (211,090) ​ $ (166,303) ​ $ (229,076) Other comprehensive earnings (loss) before reclassifications ​ ​ 79,210 ​ ​ (57,261) ​ ​ 57,364 ​ ​ (41,355) Amounts reclassified from accumulated other comprehensive earnings ​ ​ 1,083 ​ ​ 427 ​ ​ 2,415 ​ ​ 2,507 Net current-period other comprehensive earnings (loss) ​ $ 80,293 ​ $ (56,834) ​ $ 59,779 ​ $ (38,848) Ending balance ​ $ (106,524) ​ $ (267,924) ​ $ (106,524) ​ $ (267,924) Balance of securities for which an allowance for credit losses has been recognized in net earnings ​ ​ ​ ​ ​ ​ ​ $ 1,813 ​ $ 2,005 ​ Credit losses on or the sale of an available-for-sale security results in amounts being reclassified from accumulated other comprehensive earnings (loss) to current period net earnings. The effects of reclassifications out of accumulated other comprehensive earnings (loss) by the respective line items of net earnings are presented in the following table: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amount Reclassified from Accumulated Other ​ ​ ​ (in thousands) ​ Comprehensive Earnings (Loss) ​ ​ ​ ​ ​ For the Three Months ​ For the Nine Months ​ ​ ​ Component of Accumulated ​ Ended September 30, ​ Ended September 30, ​ ​ Affected line item in the Other Comprehensive Earnings (Loss) 2024 2023 2024 2023 Statement of Earnings Unrealized gains and losses on available-for-sale securities ​ $ (1,365) ​ $ (271) ​ $ (3,129) ​ $ (2,808) ​ ​ Net realized gains (losses) ​ ​ ​ (6) ​ ​ (270) ​ ​ 72 ​ ​ (365) ​ ​ Credit gains (losses) presented within net realized gains ​ ​ $ (1,371) ​ $ (541) ​ $ (3,057) ​ $ (3,173) ​ ​ Earnings (loss) before income taxes ​ ​ ​ 288 ​ ​ 114 ​ ​ 642 ​ ​ 666 ​ ​ Income tax (expense) benefit ​ ​ $ (1,083) ​ $ (427) ​ $ (2,415) ​ $ (2,507) ​ ​ Net earnings (loss) ​
Fair Value Measurements	H. FAIR VALUE MEASUREMENTS ​ Fair value is defined as the price in the principal market that would be received for an asset to facilitate an orderly transaction between market participants on the measurement date. We determined the fair value of certain financial instruments based on their underlying characteristics and relevant transactions in the marketplace. We maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. ​ The following are the levels of the fair value hierarchy and a brief description of the type of valuation inputs that are used to establish each level. Financial assets are classified based upon the lowest level of significant input that is used to determine fair value. ​ Level 1 ​ Level 2 ​ Level 3 ​ As a part of management’s process to determine fair value, we utilize widely recognized, third-party pricing sources to determine our fair values. We have obtained an understanding of the third-party pricing sources’ valuation methodologies and inputs. The following is a description of the valuation techniques used for financial assets that are measured at fair value, including the general classification of such assets pursuant to the fair value hierarchy. ​ Corporate, Agencies, Government and Municipal Bonds: ​ Mortgage-backed Securities (MBS)/Commercial Mortgage-backed Securities (CMBS) and Asset-backed Securities (ABS): ​ Regulation D Private Placement Securities: observable and unobservable inputs. Observable inputs include public corporate spread matrices classified by sector, rating and average life, as well as investment and non-investment grade matrices created from fixed income indices. Unobservable inputs include a liquidity spread premium calculated based on public corporate spread and private corporate spread matrices. The quantitative detail of the liquidity spread premium is neither provided nor reasonably available to the Company. An increase to the credit spread assumptions would result in a lower fair value. ​ For all of our fixed income securities classified as Level 2, we periodically conduct a review to assess the reasonableness of the fair values provided by our pricing services. Our review consists of a two-pronged approach. First, we compare prices provided by our pricing services to those provided by an additional source. In some cases, we obtain prices from securities brokers and compare them to the prices provided by our pricing services. If discrepancies are found in our comparisons, we compare our prices to actual reported trade data for like securities. No changes to the fair values supplied by our pricing services have occurred as a result of our reviews. Based on these assessments, we have determined that the fair values of our Level 2 fixed income securities provided by our pricing services are reasonable. ​ Equity Securities: ​ Due to the relatively short-term nature of cash, short-term investments, accounts receivable and accounts payable, their carrying amounts are reasonable estimates of fair value. Our investments in private funds, classified as other invested assets, are measured using the investments’ net asset value per share and are not categorized within the fair value hierarchy.

Basis of Presentation and Sum_3

Basis of Presentation and Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Schedule of Goodwill and Intangible Assets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, (in thousands) 2024 2023 Goodwill ​ ​ ​ ​ ​ ​ Surety ​ $ 40,816 ​ $ 40,816 Casualty ​ ​ 5,246 ​ ​ 5,246 Total goodwill ​ $ 46,062 ​ $ 46,062 Indefinite-lived intangibles ​ ​ 7,500 ​ ​ 7,500 Total goodwill and intangibles ​ $ 53,562 ​ $ 53,562
Schedule of Reconciliation of Numerator and Denominator of the Basic and Diluted Earnings Per Share Computations	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months ​ For the Three Months ​ ​ Ended September 30, 2024 ​ Ended September 30, 2023 ​ ​ Income ​ Shares ​ Per Share ​ Income ​ Shares ​ Per Share (in thousands, except per share data) (Numerator) (Denominator) Amount (Numerator) (Denominator) Amount Basic EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 95,027 ​ 45,780 ​ $ 2.08 ​ $ 13,536 ​ 45,622 ​ $ 0.30 Effect of Dilutive Securities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ ​ — ​ 440 ​ ​ ​ ​ ​ — ​ 443 ​ ​ ​ Diluted EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 95,027 ​ 46,220 ​ $ 2.06 ​ $ 13,536 ​ 46,065 ​ $ 0.29 Anti-dilutive securities excluded from diluted EPS ​ ​ ​ ​ ​ 24 ​ ​ ​ ​ ​ ​ ​ ​ 145 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Nine Months ​ For the Nine Months ​ ​ Ended September 30, 2024 ​ Ended September 30, 2023 ​ ​ Income ​ Shares ​ Per Share ​ Income ​ Shares ​ Per Share (in thousands, except per share data) (Numerator) (Denominator) Amount (Numerator) (Denominator) Amount Basic EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 304,919 ​ 45,734 ​ $ 6.67 ​ $ 189,999 ​ 45,581 ​ $ 4.17 Effect of Dilutive Securities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ ​ — ​ 451 ​ ​ ​ ​ ​ — ​ 486 ​ ​ ​ Diluted EPS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Earnings available to common shareholders ​ $ 304,919 ​ 46,185 ​ $ 6.60 ​ $ 189,999 ​ 46,067 ​ $ 4.12 Anti-dilutive securities excluded from diluted EPS ​ ​ ​ ​ ​ 24 ​ ​ ​ ​ ​ ​ ​ ​ 145 ​ ​ ​ ​
Schedule of Changes in the Balance of Each Component of Accumulated Other Comprehensive Earnings (Loss)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (in thousands) ​ For the Three Months ​ For the Nine Months ​ ​ Ended September 30, ​ Ended September 30, Unrealized Gains/Losses on Available-for-Sale Securities 2024 2023 2024 2023 Beginning balance ​ $ (186,817) ​ $ (211,090) ​ $ (166,303) ​ $ (229,076) Other comprehensive earnings (loss) before reclassifications ​ ​ 79,210 ​ ​ (57,261) ​ ​ 57,364 ​ ​ (41,355) Amounts reclassified from accumulated other comprehensive earnings ​ ​ 1,083 ​ ​ 427 ​ ​ 2,415 ​ ​ 2,507 Net current-period other comprehensive earnings (loss) ​ $ 80,293 ​ $ (56,834) ​ $ 59,779 ​ $ (38,848) Ending balance ​ $ (106,524) ​ $ (267,924) ​ $ (106,524) ​ $ (267,924) Balance of securities for which an allowance for credit losses has been recognized in net earnings ​ ​ ​ ​ ​ ​ ​ $ 1,813 ​ $ 2,005
Schedule of Effects of Reclassifications out of Accumulated Other Comprehensive Earnings (Loss)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amount Reclassified from Accumulated Other ​ ​ ​ (in thousands) ​ Comprehensive Earnings (Loss) ​ ​ ​ ​ ​ For the Three Months ​ For the Nine Months ​ ​ ​ Component of Accumulated ​ Ended September 30, ​ Ended September 30, ​ ​ Affected line item in the Other Comprehensive Earnings (Loss) 2024 2023 2024 2023 Statement of Earnings Unrealized gains and losses on available-for-sale securities ​ $ (1,365) ​ $ (271) ​ $ (3,129) ​ $ (2,808) ​ ​ Net realized gains (losses) ​ ​ ​ (6) ​ ​ (270) ​ ​ 72 ​ ​ (365) ​ ​ Credit gains (losses) presented within net realized gains ​ ​ $ (1,371) ​ $ (541) ​ $ (3,057) ​ $ (3,173) ​ ​ Earnings (loss) before income taxes ​ ​ ​ 288 ​ ​ 114 ​ ​ 642 ​ ​ 666 ​ ​ Income tax (expense) benefit ​ ​ $ (1,083) ​ $ (427) ​ $ (2,415) ​ $ (2,507) ​ ​ Net earnings (loss)

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2024
Investments Debt And Equity Securities [Abstract]
Schedule of Disposition of Fixed Income and Equity Securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Sales ​ Proceeds ​ Gross Realized ​ Net Realized (in thousands) From Sales Gains Losses Gain (Loss) 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed income securities - available-for-sale ​ $ 98,696 ​ $ 538 ​ $ (2,489) ​ $ (1,951) Equity securities ​ ​ 44,863 ​ ​ 20,276 ​ ​ (340) ​ ​ 19,936 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed income securities - available-for-sale ​ $ 25,983 ​ $ 145 ​ $ (1,035) ​ $ (890) Equity securities ​ ​ 36,708 ​ ​ 15,990 ​ ​ (101) ​ ​ 15,889 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Calls/Maturities ​ ​ ​ ​ Gross Realized ​ Net Realized (in thousands) Proceeds Gains Losses Gain (Loss) 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed income securities - available-for-sale ​ $ 240,200 ​ $ 89 ​ $ (1,062) ​ $ (973) 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed income securities - available-for-sale ​ $ 434,263 ​ $ 38 ​ $ (236) ​ $ (198)
Fair Value, Assets Measured on Recurring Basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of September 30, 2024 ​ ​ Quoted Prices in ​ Significant Other ​ Significant ​ ​ ​ ​ ​ Active Markets for ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Identical Assets ​ Inputs ​ Inputs ​ ​ ​ (in thousands) (Level 1) (Level 2) (Level 3) Total Fixed income securities - available-for-sale ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government ​ $ — ​ $ 480,207 ​ $ — ​ $ 480,207 U.S. agency ​ ​ — ​ ​ 69,111 ​ ​ — ​ ​ 69,111 Non-U.S. government & agency ​ ​ — ​ ​ 7,261 ​ ​ — ​ ​ 7,261 Agency MBS ​ ​ — ​ ​ 420,390 ​ ​ — ​ ​ 420,390 ABS/CMBS/MBS* ​ ​ — ​ ​ 361,625 ​ ​ — ​ ​ 361,625 Corporate ​ ​ — ​ ​ 1,265,857 ​ ​ 86,836 ​ ​ 1,352,693 Municipal ​ ​ — ​ ​ 484,786 ​ ​ — ​ ​ 484,786 Total fixed income securities - available-for-sale ​ $ — ​ $ 3,089,237 ​ $ 86,836 ​ $ 3,176,073 Equity securities ​ ​ 725,047 ​ ​ — ​ ​ 4,691 ​ ​ 729,738 Total ​ $ 725,047 ​ $ 3,089,237 ​ $ 91,527 ​ $ 3,905,811 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2023 ​ ​ Quoted Prices in ​ Significant Other ​ Significant ​ ​ ​ ​ ​ Active Markets for ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Identical Assets ​ Inputs ​ Inputs ​ ​ ​ (in thousands) (Level 1) (Level 2) (Level 3) Total Fixed income securities - available-for-sale ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government ​ $ — ​ $ 308,031 ​ $ — ​ $ 308,031 U.S. agency ​ ​ — ​ ​ 59,826 ​ ​ — ​ ​ 59,826 Non-U.S. government & agency ​ ​ — ​ ​ 3,882 ​ ​ — ​ ​ 3,882 Agency MBS ​ ​ — ​ ​ 425,285 ​ ​ — ​ ​ 425,285 ABS/CMBS/MBS* ​ ​ — ​ ​ 281,182 ​ ​ — ​ ​ 281,182 Corporate ​ ​ — ​ ​ 1,164,548 ​ ​ 60,471 ​ ​ 1,225,019 Municipal ​ ​ — ​ ​ 552,624 ​ ​ — ​ ​ 552,624 Total fixed income securities - available-for-sale ​ $ — ​ $ 2,795,378 ​ $ 60,471 ​ $ 2,855,849 Equity securities ​ ​ 588,416 ​ ​ — ​ ​ 1,625 ​ ​ 590,041 Total ​ $ 588,416 ​ $ 2,795,378 ​ $ 62,096 ​ $ 3,445,890 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities ​
Summary of Changes in Balance of Level 3 Securities	​ ​ ​ ​ ​ (in thousands) Level 3 Securities Balance as of January 1, 2024 ​ $ 62,096 Net realized and unrealized gains (losses) ​ ​ ​ Included in other comprehensive earnings (loss) ​ ​ 2,789 Purchases ​ ​ 28,379 Sales / Calls / Maturities ​ ​ (1,737) Balance as of September 30, 2024 ​ $ 91,527 Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - included in other comprehensive earnings (loss) ​ $ 2,789
Schedule of Contractual Maturity of Securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2024 (in thousands) Amortized Cost Fair Value Due in one year or less ​ $ 250,883 ​ $ 248,954 Due after one year through five years ​ ​ 797,980 ​ ​ 786,217 Due after five years through 10 years ​ ​ 880,694 ​ ​ 880,564 Due after 10 years ​ ​ 549,060 ​ ​ 478,323 ABS/CMBS/MBS* ​ ​ 824,067 ​ ​ 782,015 Total available-for-sale ​ $ 3,302,684 ​ $ 3,176,073 * Asset-backed, commercial mortgage-backed and mortgage-backed securities
Schedule of Amortized Cost and Fair Value of Available-for-sale Securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2024 ​ ​ Cost or ​ Allowance ​ Gross ​ Gross ​ ​ ​ ​ ​ Amortized ​ for Credit ​ Unrealized ​ Unrealized ​ Fair (in thousands) Cost Losses Gains Losses Value U.S. government ​ $ 475,022 ​ $ — ​ $ 8,012 ​ $ (2,827) ​ $ 480,207 U.S. agency ​ ​ 68,861 ​ ​ — ​ ​ 1,177 ​ ​ (927) ​ ​ 69,111 Non-U.S. government & agency ​ ​ 7,958 ​ ​ — ​ ​ 62 ​ ​ (759) ​ ​ 7,261 Agency MBS ​ ​ 446,489 ​ ​ — ​ ​ 3,877 ​ ​ (29,976) ​ ​ 420,390 ABS/CMBS/MBS* ​ ​ 377,578 ​ ​ (26) ​ ​ 3,366 ​ ​ (19,293) ​ ​ 361,625 Corporate ​ ​ 1,372,681 ​ ​ (208) ​ ​ 15,936 ​ ​ (35,716) ​ ​ 1,352,693 Municipal ​ ​ 554,095 ​ ​ — ​ ​ 1,989 ​ ​ (71,298) ​ ​ 484,786 Total Fixed Income ​ $ 3,302,684 ​ $ (234) ​ $ 34,419 ​ $ (160,796) ​ $ 3,176,073 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 ​ ​ Cost or ​ Allowance ​ Gross ​ Gross ​ ​ ​ ​ ​ Amortized ​ for Credit ​ Unrealized ​ Unrealized ​ Fair (in thousands) Cost Losses Gains Losses Value U.S. government ​ $ 312,632 ​ $ — ​ $ 1,257 ​ $ (5,858) ​ $ 308,031 U.S. agency ​ ​ 60,763 ​ ​ — ​ ​ 652 ​ ​ (1,589) ​ ​ 59,826 Non-U.S. government & agency ​ ​ 4,800 ​ ​ — ​ ​ — ​ ​ (918) ​ ​ 3,882 Agency MBS ​ ​ 460,551 ​ ​ — ​ ​ 2,636 ​ ​ (37,902) ​ ​ 425,285 ABS/CMBS/MBS* ​ ​ 308,458 ​ ​ (3) ​ ​ 611 ​ ​ (27,884) ​ ​ 281,182 Corporate ​ ​ 1,273,187 ​ ​ (303) ​ ​ 8,766 ​ ​ (56,631) ​ ​ 1,225,019 Municipal ​ ​ 634,000 ​ ​ — ​ ​ 2,238 ​ ​ (83,614) ​ ​ 552,624 Total Fixed Income ​ $ 3,054,391 ​ $ (306) ​ $ 16,160 ​ $ (214,396) ​ $ 2,855,849 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities
Schedule of Debt Securities Available-for-sale Allowance for Credit Loss	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, ​ Nine Months Ended September 30, (in thousands) 2024 2023 2024 2023 Beginning balance ​ $ 228 ​ $ 434 ​ $ 306 ​ $ 339 Increase to allowance from securities for which credit losses were not previously recorded ​ ​ 30 ​ ​ 281 ​ ​ 30 ​ ​ 25 Reduction from securities sold during the period ​ ​ — ​ ​ — ​ ​ (89) ​ ​ — Net increase (decrease) from securities that had an allowance at the beginning of the period ​ ​ (24) ​ ​ (11) ​ ​ (13) ​ ​ 340 Balance as of September 30, ​ $ 234 ​ $ 704 ​ $ 234 ​ $ 704
Schedule of Securities in an Unrealized Loss Position Segregated by Type and Length of Time in an Unrealized Loss Position	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2024 ​ December 31, 2023 (in thousands) < 12 Mos. 12 Mos. & Greater Total < 12 Mos. 12 Mos. & Greater Total U.S. government ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ — ​ $ 174,088 ​ $ 174,088 ​ $ 37,718 ​ $ 204,556 ​ $ 242,274 Amortized cost ​ ​ — ​ ​ 176,915 ​ ​ 176,915 ​ ​ 37,950 ​ ​ 210,182 ​ ​ 248,132 Unrealized loss ​ $ — ​ $ (2,827) ​ $ (2,827) ​ $ (232) ​ $ (5,626) ​ $ (5,858) U.S. agency ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 3,707 ​ $ 29,421 ​ $ 33,128 ​ $ 8,736 ​ $ 29,632 ​ $ 38,368 Amortized cost ​ ​ 3,712 ​ ​ 30,343 ​ ​ 34,055 ​ ​ 8,790 ​ ​ 31,167 ​ ​ 39,957 Unrealized loss ​ $ (5) ​ $ (922) ​ $ (927) ​ $ (54) ​ $ (1,535) ​ $ (1,589) Non-U.S. government ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 1,391 ​ $ 4,044 ​ $ 5,435 ​ $ — ​ $ 3,882 ​ $ 3,882 Amortized cost ​ ​ 1,394 ​ ​ 4,800 ​ ​ 6,194 ​ ​ — ​ ​ 4,800 ​ ​ 4,800 Unrealized Loss ​ $ (3) ​ $ (756) ​ $ (759) ​ $ — ​ $ (918) ​ $ (918) Agency MBS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 18,667 ​ $ 250,519 ​ $ 269,186 ​ $ 61,196 ​ $ 275,707 ​ $ 336,903 Amortized cost ​ ​ 18,689 ​ ​ 280,473 ​ ​ 299,162 ​ ​ 61,714 ​ ​ 313,091 ​ ​ 374,805 Unrealized loss ​ $ (22) ​ $ (29,954) ​ $ (29,976) ​ $ (518) ​ $ (37,384) ​ $ (37,902) ABS/CMBS/MBS* ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 7,744 ​ $ 177,139 ​ $ 184,883 ​ $ 12,240 ​ $ 211,436 ​ $ 223,676 Amortized cost ​ ​ 7,757 ​ ​ 196,419 ​ ​ 204,176 ​ ​ 12,367 ​ ​ 239,193 ​ ​ 251,560 Unrealized loss ​ $ (13) ​ $ (19,280) ​ $ (19,293) ​ $ (127) ​ $ (27,757) ​ $ (27,884) Corporate ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 58,742 ​ $ 740,358 ​ $ 799,100 ​ $ 67,402 ​ $ 822,731 ​ $ 890,133 Amortized cost ​ ​ 59,635 ​ ​ 775,181 ​ ​ 834,816 ​ ​ 68,345 ​ ​ 878,419 ​ ​ 946,764 Unrealized loss ​ $ (893) ​ $ (34,823) ​ $ (35,716) ​ $ (943) ​ $ (55,688) ​ $ (56,631) Municipal ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 19,725 ​ $ 386,486 ​ $ 406,211 ​ $ 61,218 ​ $ 391,361 ​ $ 452,579 Amortized cost ​ ​ 19,850 ​ ​ 457,659 ​ ​ 477,509 ​ ​ 61,697 ​ ​ 474,496 ​ ​ 536,193 Unrealized loss ​ $ (125) ​ $ (71,173) ​ $ (71,298) ​ $ (479) ​ $ (83,135) ​ $ (83,614) Total fixed income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value ​ $ 109,976 ​ $ 1,762,055 ​ $ 1,872,031 ​ $ 248,510 ​ $ 1,939,305 ​ $ 2,187,815 Amortized cost ​ ​ 111,037 ​ ​ 1,921,790 ​ ​ 2,032,827 ​ ​ 250,863 ​ ​ 2,151,348 ​ ​ 2,402,211 Unrealized loss ​ $ (1,061) ​ $ (159,735) ​ $ (160,796) ​ $ (2,353) ​ $ (212,043) ​ $ (214,396) * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities
Schedule of Credit Quality Indicators for Investments in Unrealized Loss Positions	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Equivalent ​ Equivalent ​ (dollars in thousands) ​ ​ ​ NAIC S&P Moody’s ​ Amortized ​ ​ ​ ​ Unrealized ​ Percent ​ Rating Rating Rating Cost Fair Value Loss to Total ​ 1 ​ AAA/AA/A ​ Aaa/Aa/A ​ $ 1,660,081 ​ $ 1,517,662 ​ $ (142,419) ​ 88.6 % 2 ​ BBB ​ Baa ​ ​ 321,619 ​ ​ 305,816 ​ ​ (15,803) ​ 9.8 % 3 ​ BB ​ Ba ​ ​ 25,671 ​ ​ 24,974 ​ ​ (697) ​ 0.4 % 4 ​ B ​ B ​ ​ 21,703 ​ ​ 20,562 ​ ​ (1,141) ​ 0.7 % 5 ​ CCC ​ Caa ​ ​ 2,933 ​ ​ 2,610 ​ ​ (323) ​ 0.2 % 6 ​ CC or lower ​ Ca or lower ​ ​ 820 ​ ​ 407 ​ ​ (413) ​ 0.3 % ​ ​ ​ ​ Total ​ $ 2,032,827 ​ $ 1,872,031 ​ $ (160,796) ​ 100.0 %

Historical Loss And LAE Devel_2

Historical Loss And LAE Development (Tables)	9 Months Ended
	Sep. 30, 2024
Historical Loss And L A E Development Disclosure [Abstract]
Schedule of Reconciliation of Unpaid Losses and Settlement Expenses (LAE)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Nine Months ​ ​ Ended September 30, (in thousands) 2024 2023 Unpaid losses and LAE at beginning of year ​ ​ ​ ​ ​ ​ Gross ​ $ 2,446,025 ​ $ 2,315,637 Ceded ​ ​ (757,349) ​ ​ (740,089) Net ​ $ 1,688,676 ​ $ 1,575,548 ​ ​ ​ ​ ​ ​ ​ Increase (decrease) in incurred losses and LAE ​ ​ ​ ​ ​ ​ Current accident year ​ $ 599,183 ​ $ 551,975 Prior accident years ​ ​ (85,442) ​ ​ (93,986) Total incurred ​ $ 513,741 ​ $ 457,989 ​ ​ ​ ​ ​ ​ ​ Loss and LAE payments for claims incurred ​ ​ ​ ​ ​ ​ Current accident year ​ $ (76,148) ​ $ (113,010) Prior accident years ​ ​ (273,868) ​ ​ (252,786) Total paid ​ $ (350,016) ​ $ (365,796) ​ ​ ​ ​ ​ ​ ​ Net unpaid losses and LAE at September 30, ​ $ 1,852,401 ​ $ 1,667,741 ​ ​ ​ ​ ​ ​ ​ Unpaid losses and LAE at September 30, ​ ​ ​ ​ ​ ​ Gross ​ $ 2,611,941 ​ $ 2,488,695 Ceded ​ ​ (759,540) ​ ​ (820,954) Net ​ $ 1,852,401 ​ $ 1,667,741

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2024
Income Tax Disclosure
Schedule of Reconciliation of Income Tax Expense Attributable to Income from Operations with Amounts Computed by Applying U.S. Federal Tax Rate to Pretax Income from Continuing Operations	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months Ended September 30, ​ For the Nine Months Ended September 30, 2024 ​ ​ ​ 2024 ​ 2023 ​ 2024 ​ 2023 ​ (in thousands) Amount % Amount % Amount % Amount % ​ Provision for income taxes at the statutory rate of 21% ​ $ 24,533 ​ 21.0 % $ 3,154 ​ 21.0 % $ 79,825 ​ 21.0 % $ 49,107 ​ 21.0 % Increase (reduction) in taxes resulting from: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Excess tax benefit on share-based compensation ​ ​ (1,967) ​ (1.7) % ​ (395) ​ (2.6) % ​ (4,264) ​ (1.1) % ​ (3,263) ​ (1.4) % Tax exempt interest income ​ ​ (216) ​ (0.2) % ​ (270) ​ (1.8) % ​ (725) ​ (0.2) % ​ (827) ​ (0.4) % Dividends received deduction ​ ​ (588) ​ (0.5) % ​ (164) ​ (1.1) % ​ (1,056) ​ (0.3) % ​ (597) ​ (0.3) % Tax credit ​ ​ (1,093) ​ (0.9) % ​ (779) ​ (5.2) % ​ (2,629) ​ (0.7) % ​ (2,338) ​ (1.0) % ESOP dividends paid deduction ​ ​ (149) ​ (0.1) % ​ (142) ​ (1.0) % ​ (439) ​ (0.1) % ​ (423) ​ (0.2) % Nondeductible expenses ​ ​ 1,160 ​ 1.0 % ​ 158 ​ 1.1 % ​ 2,819 ​ 0.7 % ​ 1,505 ​ 0.6 % Other items, net ​ ​ 118 ​ 0.1 % ​ (79) ​ (0.5) % ​ 1,669 ​ 0.5 % ​ 678 ​ 0.4 % Total tax expense ​ $ 21,798 ​ 18.7 % $ 1,483 ​ 9.9 % $ 75,200 ​ 19.8 % $ 43,842 ​ 18.7 %

Stock Based Compensation (Table

Stock Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2024
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Option Activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Aggregate ​ ​ ​ ​ Weighted ​ Average ​ Intrinsic ​ ​ ​ ​ Average ​ Remaining ​ Value ​ Options Exercise Price Contractual Life (in 000’s) Outstanding options at January 1, 2024 ​ 1,641,710 ​ $ 92.62 ​ ​ ​ ​ ​ Options granted ​ 165,802 ​ ​ 142.78 ​ ​ ​ ​ ​ Options exercised ​ (237,765) ​ ​ 66.39 ​ ​ ​ ​ ​ Options canceled/forfeited ​ (8,900) ​ ​ 113.28 ​ ​ ​ ​ ​ Outstanding options at September 30, 2024 ​ 1,560,847 ​ $ 101.82 ​ 4.48 ​ $ 82,970 Exercisable options at September 30, 2024 ​ 920,068 ​ $ 88.05 ​ 3.35 ​ $ 61,578
Summary of Weighted Average Grant-date Assumptions and Weighted Average Fair Values	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 ​ Weighted-average fair value of grants ​ $ 31.29 ​ $ 26.71 ​ Risk-free interest rates ​ ​ 4.92 % ​ 3.41 % Dividend yield ​ ​ 2.30 % ​ 2.29 % Expected volatility ​ ​ 23.08 % ​ 22.96 % Expected option life ​ ​ 5.00 years ​ 4.94 years
Schedule of Restricted Stock Units Activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ ​ ​ Grant Date ​ RSUs Fair Value Nonvested at January 1, 2024 ​ 45,093 ​ $ 125.16 Granted ​ 20,681 ​ ​ 143.43 Reinvested ​ 269 ​ ​ 146.77 Vested ​ (17,198) ​ ​ 122.96 Forfeited ​ (1,181) ​ ​ 134.00 Nonvested at September 30, 2024 ​ 47,664 ​ $ 133.79 ​

Operating Segment Information (

Operating Segment Information (Tables)	9 Months Ended
	Sep. 30, 2024
Segment Reporting [Abstract]
Summary of Selected Information by Operating Segment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months ​ For the Nine Months Revenues ​ Ended September 30, ​ Ended September 30, (in thousands) 2024 2023 2024 2023 Casualty ​ $ 219,638 ​ $ 189,305 ​ $ 627,014 ​ $ 562,384 Property ​ ​ 133,266 ​ ​ 94,988 ​ ​ 396,774 ​ ​ 285,596 Surety ​ ​ 36,585 ​ ​ 34,116 ​ ​ 105,442 ​ ​ 100,432 Net premiums earned ​ $ 389,489 ​ $ 318,409 ​ $ 1,129,230 ​ $ 948,412 Net investment income ​ ​ 36,694 ​ ​ 31,963 ​ ​ 103,502 ​ ​ 87,835 Net realized gains ​ ​ 5,420 ​ ​ 6,558 ​ ​ 11,222 ​ ​ 26,758 Net unrealized gains (losses) on equity securities ​ ​ 38,392 ​ ​ (25,236) ​ ​ 87,314 ​ ​ 15,474 Total consolidated revenue ​ $ 469,995 ​ $ 331,694 ​ $ 1,331,268 ​ $ 1,078,479 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net Earnings ​ ​ ​ ​ ​ ​ (in thousands) 2024 2023 2024 2023 Casualty ​ $ 2,549 ​ $ 18,670 ​ $ 26,538 ​ $ 57,478 Property ​ ​ 30,402 ​ ​ (20,671) ​ ​ 141,298 ​ ​ 33,589 Surety ​ ​ 7,741 ​ ​ 6,248 ​ ​ 20,575 ​ ​ 22,271 Net underwriting income ​ $ 40,692 ​ $ 4,247 ​ $ 188,411 ​ $ 113,338 Net investment income ​ ​ 36,694 ​ ​ 31,963 ​ ​ 103,502 ​ ​ 87,835 Net realized gains ​ ​ 5,420 ​ ​ 6,558 ​ ​ 11,222 ​ ​ 26,758 Net unrealized gains (losses) on equity securities ​ ​ 38,392 ​ ​ (25,236) ​ ​ 87,314 ​ ​ 15,474 General corporate expense and interest on debt ​ ​ (5,611) ​ ​ (4,245) ​ ​ (17,983) ​ ​ (16,733) Equity in earnings of unconsolidated investees ​ ​ 1,238 ​ ​ 1,732 ​ ​ 7,653 ​ ​ 7,169 Earnings before income taxes ​ $ 116,825 ​ $ 15,019 ​ $ 380,119 ​ $ 233,841 Income tax expense ​ ​ 21,798 ​ ​ 1,483 ​ ​ 75,200 ​ ​ 43,842 Net earnings ​ $ 95,027 ​ $ 13,536 ​ $ 304,919 ​ $ 189,999
Summary of Revenue by Major Product Type	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months ​ For the Nine Months Net Premiums Earned ​ Ended September 30, ​ Ended September 30, (in thousands) 2024 2023 2024 2023 Casualty ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial excess and personal umbrella ​ $ 91,434 ​ $ 72,559 ​ $ 257,455 ​ $ 209,402 Commercial transportation ​ ​ 32,067 ​ ​ 25,843 ​ ​ 88,691 ​ ​ 76,473 General liability ​ ​ 26,316 ​ ​ 25,250 ​ ​ 77,832 ​ ​ 77,166 Professional services ​ ​ 26,281 ​ ​ 24,882 ​ ​ 77,366 ​ ​ 73,841 Small commercial ​ ​ 20,074 ​ ​ 18,096 ​ ​ 57,870 ​ ​ 54,492 Executive products ​ ​ 6,261 ​ ​ 5,943 ​ ​ 17,624 ​ ​ 18,449 Other casualty ​ ​ 17,205 ​ ​ 16,732 ​ ​ 50,176 ​ ​ 52,561 Total ​ $ 219,638 ​ $ 189,305 ​ $ 627,014 ​ $ 562,384 Property ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial property ​ $ 85,814 ​ $ 63,783 ​ $ 260,819 ​ $ 173,264 Marine ​ ​ 37,618 ​ ​ 33,436 ​ ​ 107,255 ​ ​ 96,484 Other property ​ ​ 9,834 ​ ​ (2,231) ​ ​ 28,700 ​ ​ 15,848 Total ​ $ 133,266 ​ $ 94,988 ​ $ 396,774 ​ $ 285,596 Surety ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Transactional ​ $ 12,488 ​ $ 11,966 ​ $ 36,904 ​ $ 35,900 Commercial ​ ​ 12,477 ​ ​ 12,653 ​ ​ 35,802 ​ ​ 37,576 Contract ​ ​ 11,620 ​ ​ 9,497 ​ ​ 32,736 ​ ​ 26,956 Total ​ $ 36,585 ​ $ 34,116 ​ $ 105,442 ​ $ 100,432 Grand Total ​ $ 389,489 ​ $ 318,409 ​ $ 1,129,230 ​ $ 948,412 ​

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2024
Leases [Abstract]
Schedule of Components of Lease Expense and Other lease Information	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months ​ For the Nine Months ​ ​ Ended September 30, ​ Ended September 30, (in thousands) 2024 2023 2024 2023 Operating lease cost ​ $ 1,149 ​ $ 1,235 ​ $ 3,483 ​ $ 3,743 Variable lease cost ​ ​ 351 ​ ​ 320 ​ ​ 966 ​ ​ 1,202 Sublease income ​ ​ (42) ​ ​ (139) ​ ​ (127) ​ ​ (416) Total lease cost ​ $ 1,458 ​ $ 1,416 ​ $ 4,322 ​ $ 4,529 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash paid for amounts included in measurement of lease liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash outflows from operating leases ​ $ 845 ​ $ 1,431 ​ $ 3,013 ​ $ 4,186 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ROU assets obtained in exchange for new operating lease liabilities ​ $ 351 ​ $ 319 ​ $ 4,140 ​ $ 1,303 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Reduction to ROU assets resulting from reduction to lease liabilities ​ $ — ​ $ — ​ $ — ​ $ 200 ​ ​ ​ ​ ​ ​ ​ ​ ​ (in thousands) September 30, 2024 December 31, 2023 ​ Operating lease ROU assets ​ $ 14,768 ​ $ 13,666 ​ Operating lease liabilities ​ $ 16,384 ​ $ 14,880 ​ Weighted-average remaining lease term - operating leases ​ ​ 6.04 years ​ 6.08 years Weighted-average discount rate - operating leases ​ ​ 3.59 % ​ 3.21 % ​
Schedule of Future Minimum Lease Payments under Non-cancellable Leases	​ ​ ​ ​ ​ (in thousands) September 30, 2024 2024 ​ $ 1,070 2025 ​ ​ 4,339 2026 ​ ​ 3,633 2027 ​ ​ 2,207 2028 ​ ​ 1,537 2029 ​ ​ 1,443 Thereafter ​ ​ 4,489 Total future minimum lease payments ​ $ 18,718 Less imputed interest ​ ​ (2,334) Total operating lease liability ​ $ 16,384 ​

Basis of Presentation and Sum_4

Basis of Presentation and Summary of Significant Accounting Policies - Reinsurance - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Reinsurance
Amount of allowance for uncollectible amounts on paid recoverables	$ 16,000,000	$ 16,000,000
Reinsurance balances recoverable on unpaid losses and settlement expenses, allowances for uncollectible amounts	10,055,000	$ 10,608,000
Financing receivable, allowance for credit Loss, write-off	0
Maximum
Reinsurance
Financing receivable, allowance for credit loss, recovery	$ 1,000,000

Basis of Presentation and Sum_5

Basis of Presentation and Summary of Significant Accounting Policies - Goodwill and Intangible Assets (Details) - USD ($)	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Business Acquisition
Goodwill	$ 46,062,000	$ 46,062,000
Indefinite-lived intangibles	7,500,000	7,500,000
Total goodwill and intangibles	53,562,000	53,562,000
Goodwill and intangible asset impairment	0
Surety
Business Acquisition
Goodwill	40,816,000	40,816,000
Casualty
Business Acquisition
Goodwill	$ 5,246,000	$ 5,246,000

Basis of Presentation and Sum_6

Basis of Presentation and Summary of Significant Accounting Policies - Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Basic EPS, Income (Numerator)
Income available to common shareholders	$ 95,027	$ 13,536	$ 304,919	$ 189,999
Diluted EPS, Income (Numerator)
Income available to common shareholders	$ 95,027	$ 13,536	$ 304,919	$ 189,999
Basic EPS, Weighted Average Shares (Denominator)
Number of shares outstanding	45,780	45,622	45,734	45,581
Effect of Dilutive Securities, Shares (Denominator)
Stock options and restricted stock units	440	443	451	486
Diluted EPS, Weighted Average Shares (Denominator)
Number of shares outstanding	46,220	46,065	46,185	46,067
Earnings Per Share, Diluted, Other Disclosures
Anti-dilutive securities excluded from diluted EPS	24	145	24	145
Basic EPS, Per Share Amount
Basic net earnings per share (in dollars per share)	$ 2.08	$ 0.30	$ 6.67	$ 4.17
Diluted EPS, Per Share Amount
Diluted earnings per share (in dollars per share)	$ 2.06	$ 0.29	$ 6.60	$ 4.12

Basis of Presentation and Sum_7

Basis of Presentation and Summary of Significant Accounting Policies - Comprehensive Earnings (Loss) - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
COMPREHENSIVE EARNINGS (LOSS)
Tax rate used (as a percent)	21%			21%			21%	21%
Other comprehensive earnings (loss), tax (benefit)	$ 21,000			$ (15,000)			$ 16,000	$ (10,000)
Other comprehensive earnings (loss), net of tax	$ 80,293	$ (7,843)	$ (12,671)	$ (56,834)	$ (19,721)	$ 37,707	$ 59,779	$ (38,848)

Basis of Presentation and Sum_8

Basis of Presentation and Summary of Significant Accounting Policies - Changes in the Balance of Each Component of Accumulated Other Comprehensive Earnings (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Changes in the balance of each component of accumulated other comprehensive earnings (loss)
Beginning balance			$ (166,303)				$ (166,303)
Other comprehensive earnings (loss)	$ 80,293	$ (7,843)	(12,671)	$ (56,834)	$ (19,721)	$ 37,707	59,779	$ (38,848)
Ending balance	(106,524)						(106,524)
Unrealized Gains and Losses on Available-for-Sale Securities
Changes in the balance of each component of accumulated other comprehensive earnings (loss)
Beginning balance	(186,817)		$ (166,303)	(211,090)		$ (229,076)	(166,303)	(229,076)
Other comprehensive earnings (loss) before reclassifications	79,210			(57,261)			57,364	(41,355)
Amounts reclassified from accumulated other comprehensive earnings	1,083			427			2,415	2,507
Other comprehensive earnings (loss)	80,293			(56,834)			59,779	(38,848)
Ending balance	(106,524)	$ (186,817)		(267,924)	$ (211,090)		(106,524)	(267,924)
Balance of securities for which an allowance for credit losses has been recognized in net earnings	$ 1,813			$ 2,005			$ 1,813	$ 2,005

Basis of Presentation and Sum_9

Basis of Presentation and Summary of Significant Accounting Policies - Effects of Reclassifications out of Accumulated Other Comprehensive Earnings (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Reclassification Adjustment Out of Accumulated Other Comprehensive Income (Loss)
Earnings (loss) before income taxes	$ 116,825			$ 15,019			$ 380,119	$ 233,841
Income tax (expense) benefit	(21,798)			(1,483)			(75,200)	(43,842)
Net earnings (loss)	95,027	$ 81,992	$ 127,900	13,536	$ 77,652	$ 98,811	304,919	189,999
Unrealized Gains and Losses on Available-for-Sale Securities | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment Out of Accumulated Other Comprehensive Income (Loss)
Net realized gains (losses) - Available-for-sale	(1,365)			(271)			(3,129)	(2,808)
Credit gains (losses) presented within net realized gains	(6)			(270)			72	(365)
Earnings (loss) before income taxes	(1,371)			(541)			(3,057)	(3,173)
Income tax (expense) benefit	288			114			642	666
Net earnings (loss)	$ (1,083)			$ (427)			$ (2,415)	$ (2,507)

Investments - Disposition of Fi

Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	$ 80,245	$ 26,158
Fixed income securities - available-for-sale	242,955	414,529
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	0	(2,000)
SALES
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	98,696	25,983
Gross Realized Gains - Fixed income securities - available-for-sale	538	145
Gross Realized Losses - Fixed income securities - available-for-sale	(2,489)	(1,035)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	(1,951)	(890)
Proceeds from Sales - Equity securities	44,863	36,708
Gross Realized Gains - Equity securities	20,276	15,990
Gross Realized Losses - Equity securities	(340)	(101)
Net Realized Gain (Loss) - Equity securities	19,936	15,889
Calls And Maturities Of Marketable Securities
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	240,200	434,263
Gross Realized Gains - Fixed income securities - available-for-sale	89	38
Gross Realized Losses - Fixed income securities - available-for-sale	(1,062)	(236)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	$ (973)	$ (198)

Investments - Assets Measured a

Investments - Assets Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Assets measured at Fair Value
Available-for-sale fixed income	$ 3,176,073	$ 2,855,849
Equity securities	729,738	590,041
U.S. government
Assets measured at Fair Value
Available-for-sale fixed income	480,207	308,031
U.S. Agency
Assets measured at Fair Value
Available-for-sale fixed income	69,111	59,826
Non-U.S. government & agency
Assets measured at Fair Value
Available-for-sale fixed income	7,261	3,882
Agency MBS
Assets measured at Fair Value
Available-for-sale fixed income	420,390	425,285
ABS/CMBS/MBS
Assets measured at Fair Value
Available-for-sale fixed income	361,625	281,182
Corporate
Assets measured at Fair Value
Available-for-sale fixed income	1,352,693	1,225,019
Municipal
Assets measured at Fair Value
Available-for-sale fixed income	484,786	552,624
Fair Value Measured on Recurring Basis
Assets measured at Fair Value
Available-for-sale fixed income	3,176,073	2,855,849
Equity securities	729,738	590,041
Total assets at fair value	3,905,811	3,445,890
Fair Value Measured on Recurring Basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets measured at Fair Value
Equity securities	725,047	588,416
Total assets at fair value	725,047	588,416
Fair Value Measured on Recurring Basis | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	3,089,237	2,795,378
Total assets at fair value	3,089,237	2,795,378
Fair Value Measured on Recurring Basis | Significant Unobservable Inputs (Level 3)
Assets measured at Fair Value
Available-for-sale fixed income	86,836	60,471
Equity securities	4,691	1,625
Total assets at fair value	91,527	62,096
Fair Value Measured on Recurring Basis | U.S. government
Assets measured at Fair Value
Available-for-sale fixed income	480,207	308,031
Fair Value Measured on Recurring Basis | U.S. government | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	480,207	308,031
Fair Value Measured on Recurring Basis | U.S. Agency
Assets measured at Fair Value
Available-for-sale fixed income	69,111	59,826
Fair Value Measured on Recurring Basis | U.S. Agency | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	69,111	59,826
Fair Value Measured on Recurring Basis | Non-U.S. government & agency
Assets measured at Fair Value
Available-for-sale fixed income	7,261	3,882
Fair Value Measured on Recurring Basis | Non-U.S. government & agency | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	7,261	3,882
Fair Value Measured on Recurring Basis | Agency MBS
Assets measured at Fair Value
Available-for-sale fixed income	420,390	425,285
Fair Value Measured on Recurring Basis | Agency MBS | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	420,390	425,285
Fair Value Measured on Recurring Basis | ABS/CMBS/MBS
Assets measured at Fair Value
Available-for-sale fixed income	361,625	281,182
Fair Value Measured on Recurring Basis | ABS/CMBS/MBS | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	361,625	281,182
Fair Value Measured on Recurring Basis | Corporate
Assets measured at Fair Value
Available-for-sale fixed income	1,352,693	1,225,019
Fair Value Measured on Recurring Basis | Corporate | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	1,265,857	1,164,548
Fair Value Measured on Recurring Basis | Corporate | Significant Unobservable Inputs (Level 3)
Assets measured at Fair Value
Available-for-sale fixed income	86,836	60,471
Fair Value Measured on Recurring Basis | Municipal
Assets measured at Fair Value
Available-for-sale fixed income	484,786	552,624
Fair Value Measured on Recurring Basis | Municipal | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	$ 484,786	$ 552,624

Investments - Changes in Balanc

Investments - Changes in Balance of Level 3 Securities (Details) - Significant Unobservable Inputs (Level 3) $ in Thousands	9 Months Ended
	Sep. 30, 2024 USD ($)
Summary of changes in Level 3 securities
Beginning balance	$ 62,096
Included in other comprehensive earnings (loss)	2,789
Purchases	28,379
Sales / Calls / Maturities	(1,737)
Ending balance	91,527
Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - OCI	$ 2,789

Investments - Amortized Cost an

Investments - Amortized Cost and Fair Value of Available-for-sale Fixed Income Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Amortized Cost
Due in one year or less	$ 250,883
Due after one year through five years	797,980
Due after five years through 10 years	880,694
Due after 10 years	549,060
ABS/CMBS/MBS	824,067
Total available-for-sale	3,302,684	$ 3,054,391
Fair Value
Due in one year or less	248,954
Due after one year through five years	786,217
Due after five years through 10 years	880,564
Due after 10 years	478,323
ABS/CMBS/MBS	782,015
Total available-for-sale	$ 3,176,073	$ 2,855,849

Investments - Additional Inform

Investments - Additional Information (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2024 USD ($) security	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Investments
Accrued investment income | $	$ 26,711		$ 24,062
Number of debt securities for which there is an allowance for credit losses | security	11
Losses on fixed income securities | $	$ 0	$ 2,000
Number of debt securities in an unrealized loss position for which an allowance for credit losses has not been recorded | security	1,134
Unrealized loss | $	$ 160,796		214,396
Unrealized losses as percentage of fixed income portfolio cost basis	5%
Unrealized losses relative to total invested assets (as a percent)	4%
Number of unrealized loss positions | security	1,134
Number of securities in unrealized loss positions for 12 months or longer | security	1,045
Fixed Income Securities
Investments
Accrued investment income | $	$ 26,000		$ 23,000

Investments - Amortized Cost _2

Investments - Amortized Cost and Fair Value of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Available For Sale Securities
Cost or Amortized Cost	$ 3,302,684		$ 3,054,391
Allowance for Credit Losses	(234)	$ (228)	(306)	$ (704)	$ (434)	$ (339)
Gross Unrealized Gains	34,419		16,160
Gross Unrealized Losses	(160,796)		(214,396)
Fair Value	3,176,073		2,855,849
U.S. government
Available For Sale Securities
Cost or Amortized Cost	475,022		312,632
Gross Unrealized Gains	8,012		1,257
Gross Unrealized Losses	(2,827)		(5,858)
Fair Value	480,207		308,031
U.S. Agency
Available For Sale Securities
Cost or Amortized Cost	68,861		60,763
Gross Unrealized Gains	1,177		652
Gross Unrealized Losses	(927)		(1,589)
Fair Value	69,111		59,826
Non-U.S. government & agency
Available For Sale Securities
Cost or Amortized Cost	7,958		4,800
Gross Unrealized Gains	62
Gross Unrealized Losses	(759)		(918)
Fair Value	7,261		3,882
Agency MBS
Available For Sale Securities
Cost or Amortized Cost	446,489		460,551
Gross Unrealized Gains	3,877		2,636
Gross Unrealized Losses	(29,976)		(37,902)
Fair Value	420,390		425,285
ABS/CMBS/MBS
Available For Sale Securities
Cost or Amortized Cost	377,578		308,458
Allowance for Credit Losses	(26)		(3)
Gross Unrealized Gains	3,366		611
Gross Unrealized Losses	(19,293)		(27,884)
Fair Value	361,625		281,182
Corporate
Available For Sale Securities
Cost or Amortized Cost	1,372,681		1,273,187
Allowance for Credit Losses	(208)		(303)
Gross Unrealized Gains	15,936		8,766
Gross Unrealized Losses	(35,716)		(56,631)
Fair Value	1,352,693		1,225,019
Municipal
Available For Sale Securities
Cost or Amortized Cost	554,095		634,000
Gross Unrealized Gains	1,989		2,238
Gross Unrealized Losses	(71,298)		(83,614)
Fair Value	$ 484,786		$ 552,624

Investments - Debt Securities A

Investments - Debt Securities Available-for-sale Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Investments Debt And Equity Securities [Abstract]
Beginning balance	$ 228	$ 434	$ 306	$ 339
Increase to allowance from securities for which credit losses were not previously recorded	30	281	30	25
Reduction from securities sold during the period			(89)
Net increase (decrease) from securities that had an allowance at the beginning of the period	(24)	(11)	(13)	340
Ending balance	$ 234	$ 704	$ 234	$ 704

Investments - Securities in an

Investments - Securities in an Unrealized Loss Position Segregated by Type and Length of Time in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Fair value
Less than 12 months	$ 109,976	$ 248,510
12 months and greater	1,762,055	1,939,305
Total Fair Value	1,872,031	2,187,815
Amortized Cost
Amortized cost, less than 12 months	111,037	250,863
12 months and greater	1,921,790	2,151,348
Total Cost or Amortized Cost	2,032,827	2,402,211
Unrealized Loss
Less than 12 months	(1,061)	(2,353)
12 months and greater	(159,735)	(212,043)
Total Unrealized Loss	(160,796)	(214,396)
U.S. government
Fair value
Less than 12 months		37,718
12 months and greater	174,088	204,556
Total Fair Value	174,088	242,274
Amortized Cost
Amortized cost, less than 12 months		37,950
12 months and greater	176,915	210,182
Total Cost or Amortized Cost	176,915	248,132
Unrealized Loss
Less than 12 months		(232)
12 months and greater	(2,827)	(5,626)
Total Unrealized Loss	(2,827)	(5,858)
U.S. Agency
Fair value
Less than 12 months	3,707	8,736
12 months and greater	29,421	29,632
Total Fair Value	33,128	38,368
Amortized Cost
Amortized cost, less than 12 months	3,712	8,790
12 months and greater	30,343	31,167
Total Cost or Amortized Cost	34,055	39,957
Unrealized Loss
Less than 12 months	(5)	(54)
12 months and greater	(922)	(1,535)
Total Unrealized Loss	(927)	(1,589)
Non-U.S. government & agency
Fair value
Less than 12 months	1,391
12 months and greater	4,044	3,882
Total Fair Value	5,435	3,882
Amortized Cost
Amortized cost, less than 12 months	1,394
12 months and greater	4,800	4,800
Total Cost or Amortized Cost	6,194	4,800
Unrealized Loss
Less than 12 months	(3)
12 months and greater	(756)	(918)
Total Unrealized Loss	(759)	(918)
Agency MBS
Fair value
Less than 12 months	18,667	61,196
12 months and greater	250,519	275,707
Total Fair Value	269,186	336,903
Amortized Cost
Amortized cost, less than 12 months	18,689	61,714
12 months and greater	280,473	313,091
Total Cost or Amortized Cost	299,162	374,805
Unrealized Loss
Less than 12 months	(22)	(518)
12 months and greater	(29,954)	(37,384)
Total Unrealized Loss	(29,976)	(37,902)
ABS/CMBS/MBS
Fair value
Less than 12 months	7,744	12,240
12 months and greater	177,139	211,436
Total Fair Value	184,883	223,676
Amortized Cost
Amortized cost, less than 12 months	7,757	12,367
12 months and greater	196,419	239,193
Total Cost or Amortized Cost	204,176	251,560
Unrealized Loss
Less than 12 months	(13)	(127)
12 months and greater	(19,280)	(27,757)
Total Unrealized Loss	(19,293)	(27,884)
Corporate
Fair value
Less than 12 months	58,742	67,402
12 months and greater	740,358	822,731
Total Fair Value	799,100	890,133
Amortized Cost
Amortized cost, less than 12 months	59,635	68,345
12 months and greater	775,181	878,419
Total Cost or Amortized Cost	834,816	946,764
Unrealized Loss
Less than 12 months	(893)	(943)
12 months and greater	(34,823)	(55,688)
Total Unrealized Loss	(35,716)	(56,631)
Municipal
Fair value
Less than 12 months	19,725	61,218
12 months and greater	386,486	391,361
Total Fair Value	406,211	452,579
Amortized Cost
Amortized cost, less than 12 months	19,850	61,697
12 months and greater	457,659	474,496
Total Cost or Amortized Cost	477,509	536,193
Unrealized Loss
Less than 12 months	(125)	(479)
12 months and greater	(71,173)	(83,135)
Total Unrealized Loss	$ (71,298)	$ (83,614)

Investments - Unrealized Losses

Investments - Unrealized Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Cost or amortized Cost
Total Cost or Amortized Cost	$ 2,032,827	$ 2,402,211
Fair value
Total Fair Value	1,872,031	2,187,815
Unrealized Loss
Total Unrealized Loss	$ (160,796)	$ (214,396)
Percent to Total	100%
NAIC Rating 1 | AAA/AA/A | Aaa/Aa/A
Cost or amortized Cost
Total Cost or Amortized Cost	$ 1,660,081
Fair value
Total Fair Value	1,517,662
Unrealized Loss
Total Unrealized Loss	$ (142,419)
Percent to Total	88.60%
NAIC Rating 2 | BBB | Baa
Cost or amortized Cost
Total Cost or Amortized Cost	$ 321,619
Fair value
Total Fair Value	305,816
Unrealized Loss
Total Unrealized Loss	$ (15,803)
Percent to Total	9.80%
NAIC Rating 3 | BB | Ba
Cost or amortized Cost
Total Cost or Amortized Cost	$ 25,671
Fair value
Total Fair Value	24,974
Unrealized Loss
Total Unrealized Loss	$ (697)
Percent to Total	0.40%
NAIC Rating 4 | B | B
Cost or amortized Cost
Total Cost or Amortized Cost	$ 21,703
Fair value
Total Fair Value	20,562
Unrealized Loss
Total Unrealized Loss	$ (1,141)
Percent to Total	0.70%
NAIC Rating 5 | CCC | Caa
Cost or amortized Cost
Total Cost or Amortized Cost	$ 2,933
Fair value
Total Fair Value	2,610
Unrealized Loss
Total Unrealized Loss	$ (323)
Percent to Total	0.20%
NAIC Rating 6 | CC Or Lower | Ca or lower
Cost or amortized Cost
Total Cost or Amortized Cost	$ 820
Fair value
Total Fair Value	407
Unrealized Loss
Total Unrealized Loss	$ (413)
Percent to Total	0.30%

Investments - Debt and Short-te

Investments - Debt and Short-term Investments (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Investments
Other investments	$ 53,993,000		$ 53,993,000		$ 59,081,000
Investment in unconsolidated investees	65,271,000		65,271,000		56,966,000
Cash and Short-term Investments
Cash	60,634,000		60,634,000		36,424,000
Short-term investments	203,296,000		203,296,000		134,923,000
Other Unconsolidated Investees | Maximum
Investments
Investment in unconsolidated investees	1,000,000		1,000,000
Prime Holdings Insurance Services, Inc. (Prime)
Investments
Investment in unconsolidated investees	65,000,000		65,000,000
Dividends received from investments in unconsolidated investees			3,000,000		0
FHLBC
Investments
Investments pledged as collateral	$ 57,000,000		$ 57,000,000
Investment in federal home loan bank stock	us-gaap:AssetPledgedAsCollateralMember		us-gaap:AssetPledgedAsCollateralMember
Federal home loan bank borrowings fair value disclosure	$ 50,000,000		$ 50,000,000
Investment In Low Income Housing Tax Credit Partnerships (LIHTC)
Investments
Other investments	8,000,000		8,000,000		10,000,000
Amortization on low income housing investments	$ 1,000,000	$ 1,000,000	$ 2,000,000	$ 2,000,000
Amortization of tax credit partnerships, Statement of Income	Income tax expense	Income tax expense	Income tax expense	Income tax expense
Total tax benefit on investments in tax credit partnership	$ 1,000,000	$ 1,000,000	$ 2,000,000	$ 2,000,000
Investment In Low Income Housing Tax Credit Partnerships (LIHTC) | Maximum
Investments
Qualified affordable housing project investments, unfunded commitment	1,000,000		1,000,000
Historic tax credit partnerships (HTC)
Investments
Other investments	9,000,000		9,000,000		13,000,000
Amortization on qualifying equity investments	$ 1,000,000	$ 1,000,000	$ 3,000,000	$ 3,000,000
Amortization of tax credit partnerships, Statement of Income	Income tax expense	Income tax expense	Income tax expense	Income tax expense
Total tax benefit on investments in tax credit partnership	$ 2,000,000	$ 1,000,000	$ 4,000,000	$ 4,000,000
Investment in Private Funds
Investments
Other investments	25,000,000		25,000,000		$ 28,000,000
Fair value investments entities that calculate net asset value per share, unfunded commitments	$ 4,000,000		$ 4,000,000

Historical Loss and LAE Devel_3

Historical Loss and LAE Development - Reconciliation of Unpaid Losses and Settlement Expenses (LAE) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Unpaid losses and LAE at beginning of year
Gross	$ 2,446,025	$ 2,315,637
Ceded	(757,349)	(740,089)
Net	1,688,676	1,575,548
Increase (decrease) in incurred losses and LAE
Current accident year	599,183	551,975
Prior accident years	(85,442)	(93,986)
Total incurred	513,741	457,989
Loss and LAE payments for claims incurred
Current accident year	(76,148)	(113,010)
Prior accident years	(273,868)	(252,786)
Total paid	(350,016)	(365,796)
Net unpaid losses and LAE at June 30	1,852,401	1,667,741
Unpaid losses and LAE at June 30
Gross	2,611,941	2,488,695
Ceded	(759,540)	(820,954)
Net unpaid losses and LAE at June 30	$ 1,852,401	$ 1,667,741

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Tax Disclosure
Effective income tax rate reconciliation, percent, total	18.70%	9.90%	19.80%	18.70%
U.S. federal tax rate	21%	21%	21%	21%

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Income Tax Expense (Benefit) Attributable to Income from Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Reconciliation of income tax expense reported to amount computed by applying the U.S. federal tax rate
Provision for income taxes at the statutory federal rate	$ 24,533	$ 3,154	$ 79,825	$ 49,107
Increase (reduction) in taxes resulting from:
Excess tax benefit on share-based compensation	(1,967)	(395)	(4,264)	(3,263)
Tax exempt interest income	(216)	(270)	(725)	(827)
Dividends received deduction	(588)	(164)	(1,056)	(597)
Tax credit	(1,093)	(779)	(2,629)	(2,338)
ESOP dividends paid deduction	(149)	(142)	(439)	(423)
Nondeductible expenses	1,160	158	2,819	1,505
Other items, net	118	(79)	1,669	678
Income tax expense	$ 21,798	$ 1,483	$ 75,200	$ 43,842
Reconciliation of income tax expense rate to the U.S. federal tax rate
Tax rate used (as a percent)	21%	21%	21%	21%
Excess tax benefit on share-based compensation (as a percent)	(1.70%)	(2.60%)	(1.10%)	(1.40%)
Effective rate reduction due to tax exempt interest income (as a percent)	(0.20%)	(1.80%)	(0.20%)	(0.40%)
Effective rate reduction due to dividend received (as a percent)	(0.50%)	(1.10%)	(0.30%)	(0.30%)
Effective rate reduction due to tax credit (as a percent)	(0.90%)	(5.20%)	(0.70%)	(1.00%)
Effective rate reduction due to dividend paid to ESOP (as a percent)	(0.10%)	(1.00%)	(0.10%)	(0.20%)
Effective rate reduction due to nondeductible expenses (as a percent)	1%	1.10%	0.70%	0.60%
Effective rate reduction due to other items, net (as a percent)	0.10%	(0.50%)	0.50%	0.40%
Total tax expense (as a percent)	18.70%	9.90%	19.80%	18.70%

Stock Based Compensation - Stoc

Stock Based Compensation - Stock Plans - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		17 Months Ended	96 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	May 03, 2023	May 04, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Options granted (in shares)			165,802
RLI Corp. Long-Term Incentive Plans
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expenses	$ 2	$ 2	$ 6	$ 7
Income tax benefit from stock-based compensation			1	$ 1
Unrecognized stock-based compensation expense	8		$ 8		$ 8
Stock-based compensation expenses, recognition period			2 years 7 months 20 days
RLI Corp. Long-Term Incentive Plans | Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Income tax benefit from stock-based compensation	$ 1	$ 1
RLI Corp. Long-Term Incentive Plans | Employee Stock Option
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Award vesting period			5 years
Term of options			8 years
RLI Corp. Long-Term Incentive Plans | Employee Stock Option | Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Age and period of service of the participant to be eligible for retirement			75 years
RLI Corp. Long-Term Incentive Plan (2015 LTIP)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares authorized for grant						4,000,000
Options granted (in shares)						3,291,388
RLI Corp. Long-Term Incentive Plan (2023 LTIP)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares authorized for grant							4,004,891
Options granted (in shares)			186,483		382,021

Stock Based Compensation - Summ

Stock Based Compensation - Summary of Option Activity (Details) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2024 USD ($) $ / shares shares	Sep. 30, 2023 USD ($)
Weighted Number of Options Outstanding
Outstanding options, Beginning Balance | shares	1,641,710
Options granted (in shares) | shares	165,802
Options exercised | shares	(237,765)
Options canceled/forfeited | shares	(8,900)
Outstanding options, Ending Balance | shares	1,560,847
Exercisable options, Ending Balance | shares	920,068
Weighted Average Exercise Price
Weighted Average Exercise Price, Outstanding options, Beginning Balance | $ / shares	$ 92.62
Weighted Average Exercise Price, Options granted | $ / shares	142.78
Weighted Average Exercise Price, Options exercised | $ / shares	66.39
Weighted Average Exercise Price, Options canceled/forfeited | $ / shares	113.28
Weighted Average Exercise Price, Outstanding options, Ending Balance | $ / shares	101.82
Weighted Average Exercise Price, Exercisable options | $ / shares	$ 88.05
Weighted Average Remaining Contractual Life
Weighted Average Remaining Contractual Life, Outstanding options	4 years 5 months 23 days
Weighted Average Remaining Contractual Life, Exercisable options	3 years 4 months 6 days
Aggregate Intrinsic Value, Options exercised | $	$ 19,000	$ 17,000
Aggregate Intrinsic Value, Outstanding options | $	82,970
Aggregate Intrinsic Value, Exercisable options | $	$ 61,578

Stock Based Compensation - Su_2

Stock Based Compensation - Summary of Weighted Average Grant-date Assumptions and Weighted Average Fair Values (Details) - $ / shares	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Weighted average grant date assumptions and weighted average fair value
Weighted-average fair value of grants	$ 31.29	$ 26.71
Risk-free interest rates	4.92%	3.41%
Dividend yield	2.30%	2.29%
Expected volatility	23.08%	22.96%
Expected option life	5 years	4 years 11 months 8 days

Stock Based Compensation - Rest

Stock Based Compensation - Restricted Stock Units - Additional Information (Details) - Restricted Stock Units (RSUs) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Share Based Compensation
Fair value of restricted stock units vested	$ 2	$ 3
Minimum
Share Based Compensation
Age and period of service of the participant to be eligible for retirement	75 years
Employees
Share Based Compensation
Award vesting period	3 years
Directors
Share Based Compensation
Award vesting period	1 year

Stock Based Compensation - Sche

Stock Based Compensation - Schedule of Restricted Stock Units Activity (Details)	9 Months Ended
	Sep. 30, 2024 $ / shares shares
Number of RSUs
RSUs Nonvested, Beginning Balance | shares	45,093
RSUs Granted | shares	20,681
RSUs Reinvested | shares	269
RSUs Vested | shares	(17,198)
RSUs Forfeited | shares	(1,181)
RSUs Nonvested, Ending Balance | shares	47,664
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Nonvested, Beginning Balance | $ / shares	$ 125.16
Weighted Average Grant Date Fair Value, Granted | $ / shares	143.43
Weighted Average Grant Date Fair Value, Reinvested | $ / shares	146.77
Weighted Average Grant Date Fair Value, Vested | $ / shares	122.96
Weighted Average Grant Date Fair Value, Forfeited | $ / shares	134
Weighted Average Grant Date Fair Value, Nonvested, Ending Balance | $ / shares	$ 133.79

Operating Segment Information -

Operating Segment Information - Summary by Operating Segment (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenues
Net premiums earned	$ 389,489			$ 318,409			$ 1,129,230	$ 948,412
Net investment income	36,694			31,963			103,502	87,835
Net realized gains	5,420			6,558			11,222	26,758
Net unrealized gains (losses) on equity securities	38,392			(25,236)			87,314	15,474
Consolidated revenue	469,995			331,694			1,331,268	1,078,479
Net Earnings
Net underwriting income	40,692			4,247			188,411	113,338
Net investment income	36,694			31,963			103,502	87,835
Net realized gains	5,420			6,558			11,222	26,758
Net unrealized gains (losses) on equity securities	38,392			(25,236)			87,314	15,474
General corporate expense and interest on debt	(5,611)			(4,245)			(17,983)	(16,733)
Equity in earnings of unconsolidated investees	1,238			1,732			7,653	7,169
Earnings (loss) before income taxes	116,825			15,019			380,119	233,841
Income tax expense	21,798			1,483			75,200	43,842
Net earnings (loss)	95,027	$ 81,992	$ 127,900	13,536	$ 77,652	$ 98,811	304,919	189,999
Casualty Segment
Revenues
Net premiums earned	219,638			189,305			627,014	562,384
Net Earnings
Net underwriting income	2,549			18,670			26,538	57,478
Property Segment
Revenues
Net premiums earned	133,266			94,988			396,774	285,596
Net Earnings
Net underwriting income	30,402			(20,671)			141,298	33,589
Surety Segment
Revenues
Net premiums earned	36,585			34,116			105,442	100,432
Net Earnings
Net underwriting income	$ 7,741			$ 6,248			$ 20,575	$ 22,271

Operating Segment Information_2

Operating Segment Information - Summary of Revenue by Major Product Type (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment Reporting
Net premiums earned	$ 389,489	$ 318,409	$ 1,129,230	$ 948,412
Casualty Segment
Segment Reporting
Net premiums earned	219,638	189,305	627,014	562,384
Casualty Segment | Commercial excess and personal umbrella
Segment Reporting
Net premiums earned	91,434	72,559	257,455	209,402
Casualty Segment | Commercial transportation
Segment Reporting
Net premiums earned	32,067	25,843	88,691	76,473
Casualty Segment | General liability
Segment Reporting
Net premiums earned	26,316	25,250	77,832	77,166
Casualty Segment | Professional services
Segment Reporting
Net premiums earned	26,281	24,882	77,366	73,841
Casualty Segment | Small commercial
Segment Reporting
Net premiums earned	20,074	18,096	57,870	54,492
Casualty Segment | Executive products
Segment Reporting
Net premiums earned	6,261	5,943	17,624	18,449
Casualty Segment | Other casualty
Segment Reporting
Net premiums earned	17,205	16,732	50,176	52,561
Property Segment
Segment Reporting
Net premiums earned	133,266	94,988	396,774	285,596
Property Segment | Commercial property
Segment Reporting
Net premiums earned	85,814	63,783	260,819	173,264
Property Segment | Marine
Segment Reporting
Net premiums earned	37,618	33,436	107,255	96,484
Property Segment | Other property
Segment Reporting
Net premiums earned	9,834	(2,231)	28,700	15,848
Surety Segment
Segment Reporting
Net premiums earned	36,585	34,116	105,442	100,432
Surety Segment | Transactional
Segment Reporting
Net premiums earned	12,488	11,966	36,904	35,900
Surety Segment | Commercial
Segment Reporting
Net premiums earned	12,477	12,653	35,802	37,576
Surety Segment | Contract
Segment Reporting
Net premiums earned	$ 11,620	$ 9,497	$ 32,736	$ 26,956

Leases - Schedule of Components

Leases - Schedule of Components of Lease Expense and Other lease Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Leases [Abstract]
Operating lease cost	$ 1,149	$ 1,235	$ 3,483	$ 3,743
Variable lease cost	351	320	966	1,202
Sublease income	(42)	(139)	(127)	(416)
Total lease cost	1,458	1,416	4,322	4,529
Cash paid for amounts included in measurement of lease liabilities
Operating cash outflows from operating leases	845	1,431	3,013	4,186
ROU assets obtained in exchange for new operating lease liabilities	351	$ 319	4,140	1,303
Reduction to ROU assets resulting from reduction to lease liabilities				$ 200
Operating lease ROU assets	$ 14,768		$ 14,768		$ 13,666
Operating Lease, Right-of-Use Asset, Statement of Financial Position	Other assets		Other assets		Other assets
Operating lease liabilities	$ 16,384		$ 16,384		$ 14,880
Operating Lease, Liability, Statement of Financial Position	Other liabilities		Other liabilities		Other liabilities
Weighted-average remaining lease term - operating leases	6 years 14 days		6 years 14 days		6 years 29 days
Weighted-average discount rate - operating leases	3.59%		3.59%		3.21%

Leases - Schedule of Future Min

Leases - Schedule of Future Minimum Lease Payments under Non-cancellable Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Future minimum lease payments under non-cancellable leases
2024	$ 1,070
2025	4,339
2026	3,633
2027	2,207
2028	1,537
2029	1,443
Thereafter	4,489
Total future minimum lease payments	18,718
Less imputed interest	(2,334)
Operating lease liabilities	$ 16,384	$ 14,880

Acquisitions and Dispositions (

Acquisitions and Dispositions (Details) $ in Millions	3 Months Ended
	Mar. 31, 2023 USD ($)
Maui Jim Inc. | Net Realized Gains
Dispositions
Recognized gain on sale	$ 14

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event - Hurricane Milton - Insurance claims $ in Millions	Oct. 23, 2024 USD ($)
Minimum
Subsequent Events
Estimated losses, net of reinsurance benefits	$ 45
Maximum
Subsequent Events
Estimated losses, net of reinsurance benefits	$ 55