Consolidated Statements Of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues
Net earned premiums	$ 8,350,997	$ 8,632,142	$ 7,759,796
Net investment income	626,217	656,429	650,296
Net realized gains on investments, excluding other-than-temporary impairment losses	36,850	60,813	38,912
Total other-than-temporary impairment losses	(7,212)	(69)	(4,516)
Portion of net loss recognized in other comprehensive income, before taxes	2,188	39	129
Net other-than-temporary impairment losses recognized in earnings	(5,024)	(30)	(4,387)
Amortization of deferred gain on disposal of businesses	12,988	(1,506)	16,310
Fees and other income	1,303,466	1,033,805	586,730
Total revenues	10,325,494	10,381,653	9,047,657
Benefits, losses and expenses
Policyholder benefits	4,742,535	4,405,333	3,675,532
Amortization of deferred acquisition costs and value of business acquired	1,402,573	1,485,558	1,470,287
Underwriting, general and administrative expenses	3,924,089	3,688,230	3,034,404
Interest expense	55,116	58,395	77,735
Total benefits, losses and expenses	10,124,313	9,637,516	8,257,958
Income before benefit for income taxes	201,181	744,137	789,699
Provision for income taxes	59,626	273,230	300,792
Net income	$ 141,555	$ 470,907	$ 488,907
Earnings Per Share
Basic (in dollars per share)	$ 2.08	$ 6.52	$ 6.38
Diluted (in dollars per share)	2.05	6.44	6.30
Dividends per share (in dollars per share)	$ 1.37	$ 1.06	$ 0.96
Share Data
Weighted average shares outstanding used in basic per share calculations (in shares)	68,163,825	72,181,447	76,648,688
Plus: Dilutive securities (in shares)	853,384	970,563	1,006,076
Weighted average shares used in diluted per share calculations (in shares)	69,017,209	73,152,010	77,654,764