Condensed Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 450	$ 314	$ 1,015	$ 1,175
Other comprehensive (loss) income:
Change in gross unrealized investment gains/losses	(9)	25	150	(48)
Effect of income taxes	3	(9)	(55)	18
Total change in unrealized investment gains/losses, net of tax	(6)	16	95	(30)
Reclassification adjustment for net realized gains included in investment income	(26)	(51)	(65)	(88)
Effect of income taxes	10	19	24	32
Total reclassification adjustment, net of tax	(16)	(32)	(41)	(56)
Other comprehensive (loss) income, net of tax	(22)	(16)	54	(86)
Comprehensive income	$ 428	$ 298	$ 1,069	$ 1,089