Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Revenues
Net premiums earned (Note 8)	$ 237,731	$ 213,429	$ 473,588	$ 446,667
Services revenue (Note 4)	13,265	11,797	25,853	22,781
Net investment income (Note 6)	73,766	63,348	142,987	121,801
Net gains (losses) on investments and other financial instruments (includes net realized gains (losses) on investments of $(3,019), $(3,355), $(6,701) and $(8,861)) (Note 6)	(4,487)	(236)	(3,997)	5,349
Other income	872	1,241	2,134	2,833
Total revenues	321,147	289,579	640,565	599,431
Expenses
Provision for losses (Note 11)	(1,745)	(21,632)	(8,779)	(38,561)
Policy acquisition costs	6,522	5,218	13,316	11,511
Cost of services	9,535	10,257	18,862	20,655
Other operating expenses	91,648	89,885	174,284	173,154
Interest expense (Note 12)	27,064	21,805	56,110	43,244
Amortization of other acquired intangible assets	0	1,370	0	2,741
Total expenses	133,024	106,903	253,793	212,744
Pretax income	188,123	182,676	386,772	386,687
Income tax provision	36,220	36,589	82,515	82,843
Net income	$ 151,903	$ 146,087	$ 304,257	$ 303,844
Net income per share
Basic (in usd per share)	$ 0.99	$ 0.92	$ 1.98	$ 1.91
Diluted (in usd per share)	$ 0.98	$ 0.91	$ 1.96	$ 1.89
Weighted average number of common shares outstanding—basic (in shares)	153,110	159,010	153,879	159,250
Weighted average number of common and common equivalent shares outstanding—diluted (in shares)	154,399	160,744	155,271	161,129