Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Revenues:
Net premiums earned—insurance (Note 8)	$ 1,145,349		$ 1,014,007		$ 932,773
Services revenue (Note 4)	154,596		144,972		155,103
Net investment income (Note 6)	171,796		152,475		127,248
Net gains (losses) on investments and other financial instruments	51,719		(42,476)		3,621
Other income	3,495		4,028		2,886
Total revenues	1,526,955		1,273,006		1,221,631
Expenses:
Provision for losses	132,031		104,641		135,154
Policy acquisition costs	25,314		25,265		24,277
Cost of services	108,324		98,124		104,599
Other operating expenses	306,129		280,818		267,321
Restructuring and other exit costs	0		6,053		17,268
Interest expense	56,310		61,490		62,761
Loss on extinguishment of debt (Note 12)	22,738		0		51,469
Impairment of goodwill (Note 7)	4,828		0		184,374
Amortization and impairment of other acquired intangible assets	22,288		12,429		27,671
Total expenses	677,962		588,820		874,894
Pretax income	848,993		684,186		346,737
Income tax provision (Note 10)	176,684		78,175		225,649
Net income	$ 672,309		$ 606,011		$ 121,088
Earnings Per Share, Basic:
Net income (loss), per basic share	$ 3.22		$ 2.83		$ 0.56
Earnings Per Share, Diluted:
Net income (loss) per diluted share	$ 3.20	[1]	$ 2.77	[1]	$ 0.55
Weighted-average number of common shares outstanding—basic	208,773		214,267		215,321
Weighted-average number of common and common equivalent shares outstanding—diluted	210,340		218,553		220,406

[1] Diluted net income per share is computed independently for each period presented. Consequently, the sum of the quarters may not equal the total net income per share for the year.