Condensed Consolidated Statements of Earnings and Comprehensive Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Statement [Abstract]
Net premiums earned	$ 322,280	$ 282,810	$ 630,003	$ 551,962
Net investment income	28,788	18,472	55,872	36,355
Net realized gains	5,580	12,804	20,200	18,392
Net unrealized gains (losses) on equity securities	25,214	(100,994)	40,710	(128,804)
Consolidated revenue	381,862	213,092	746,785	477,905
Losses and settlement expenses	153,943	117,914	268,431	223,438
Policy acquisition costs	102,626	89,615	204,070	174,902
Insurance operating expenses	24,510	19,325	48,411	38,188
Interest expense on debt	2,047	2,011	4,055	4,021
General corporate expenses	4,219	2,435	8,433	5,798
Total expenses	287,345	231,300	533,400	446,347
Equity in earnings of unconsolidated investees	1,514	11,654	5,437	20,413
Earnings (loss) before income taxes	96,031	(6,554)	218,822	51,971
Income tax expense (benefit)	18,379	(4,315)	42,359	6,287
Net earnings (loss)	77,652	(2,239)	176,463	45,684
Other comprehensive earnings (loss), net of tax	(19,721)	(97,563)	17,986	(213,144)
Comprehensive earnings (loss)	$ 57,931	$ (99,802)	$ 194,449	$ (167,460)
Basic net earnings (loss) per share	$ 1.70	$ (0.05)	$ 3.87	$ 1.01
Diluted net earnings (loss) per share	$ 1.69	$ (0.05)	$ 3.83	$ 1.00
Weighted average number of common shares outstanding:
Basic	45,591	45,354	45,560	45,330
Diluted	46,044	45,354	46,045	45,748