CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
Net premiums	$ 2,809,641	$ 2,562,042	$ 8,311,240	$ 7,739,053
Investment income, net of related expenses	678,805	572,742	1,842,760	1,617,132
Investment related gains (losses), net:
Other-than-temporary impairments on fixed maturity securities	(8,539)	(10,705)	(17,992)	(14,055)
Other investment related gains (losses), net	57,323	(9,312)	87,036	(17,004)
Total investment related gains (losses), net	48,784	(20,017)	69,044	(31,059)
Other revenues	90,335	112,764	291,960	272,020
Total revenues	3,627,565	3,227,531	10,515,004	9,597,146
Benefits and Expenses:
Claims and other policy benefits	2,469,981	2,209,920	7,493,516	6,851,614
Interest credited	226,262	143,292	517,293	333,068
Policy acquisition costs and other insurance expenses	321,855	310,639	894,081	987,817
Other operating expenses	209,348	200,262	634,330	586,495
Interest expense	45,927	33,290	129,383	107,769
Collateral finance and securitization expense	7,102	7,467	22,670	22,509
Total benefits and expenses	3,280,475	2,904,870	9,691,273	8,889,272
Income before income taxes	347,090	322,661	823,731	707,874
Provision for income taxes	84,325	21,462	188,761	102,071
Net income	$ 262,765	$ 301,199	$ 634,970	$ 605,803
Earnings per share:
Basic earnings per share	$ 4.19	$ 4.76	$ 10.13	$ 9.47
Diluted earnings per share	$ 4.12	$ 4.68	$ 9.93	$ 9.30