Condensed Consolidated Statements of Earnings and Comprehensive Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Income Statement [Abstract]
Net premiums earned	$ 411,386	$ 398,345
Net investment income	42,321	36,726
Net realized gains	9,559	14,912
Net unrealized gains (losses) on equity securities	(39,396)	(42,318)
Consolidated revenue	423,870	407,665
Losses and settlement expenses	193,244	177,238
Policy acquisition costs	132,075	123,687
Insurance operating expenses	28,280	26,874
Interest expense on debt	2,353	1,335
General corporate expenses	2,724	2,948
Total expenses	358,676	332,082
Equity in earnings of unconsolidated investees	2,147	3,048
Earnings before income taxes	67,341	78,631
Income tax expense	12,456	15,417
Net earnings	54,885	63,214
Other comprehensive earnings (loss), net of tax	(25,366)	30,030
Comprehensive earnings	$ 29,519	$ 93,244
Basic net earnings per share (in dollars per share)	$ 0.6	$ 0.69
Diluted net earnings per share (in dollars per share)	$ 0.6	$ 0.68
Weighted average number of common shares outstanding:
Basic weighted average number of common shares outstanding (in shares)	91,926	91,770
Diluted weighted average number of common shares outstanding (in shares)	92,187	92,528