Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenues
Net premiums earned (Note 8)	$ 253,892	$ 254,756	$ 508,082	$ 526,628
Services revenue (Note 4)	27,281	29,464	56,629	52,359
Net investment income	46,957	36,291	85,153	74,542
Net gains (losses) on investments and other financial instruments (includes net realized gains (losses) on investments of $(3,992), $4,266, $(4,315) and $4,084) (Note 6)	(41,869)	15,661	(71,326)	10,480
Other income	572	822	1,275	1,798
Total revenues	286,833	336,994	579,813	665,807
Expenses
Provision for losses	(113,922)	3,648	(197,676)	49,791
Policy acquisition costs	5,940	4,838	12,545	13,834
Cost of services	22,760	24,615	47,513	44,861
Other operating expenses	90,495	86,469	180,036	156,731
Interest expense	20,831	21,065	41,677	42,180
Amortization of other acquired intangible assets	849	863	1,698	1,725
Total expenses	26,953	141,498	85,793	309,122
Pretax income	259,880	195,496	494,020	356,685
Income tax provision	58,687	40,290	111,696	75,871
Net income	$ 201,193	$ 155,206	$ 382,324	$ 280,814
Net Income Per Share
Basic net income per share (in usd per share)	$ 1.16	$ 0.80	$ 2.18	$ 1.45
Diluted net income per share (in usd per share)	$ 1.15	$ 0.80	$ 2.16	$ 1.44
Weighted-average number of common shares outstanding—basic (in shares)	173,705	193,436	175,491	193,692
Weighted-average number of common and common equivalent shares outstanding—diluted (in shares)	175,419	194,638	177,349	194,986