Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Pre- tax
Unrealized net holding gains and losses arising during the period, net of related offsets	$ 97	$ (286)	$ 763	$ (726)
Less: reclassification adjustment of realized capital gains and losses	(15)	178	(78)	346
Unrealized net capital gains and losses	112	(464)	841	(1,072)
Unrealized foreign currency translation adjustments	(4)	5	2	(6)
Other comprehensive income (loss)	108	(459)	843	(1,078)
Tax
Unrealized net holding gains and losses arising during the period, net of related offsets	(34)	224	(267)	496
Less: reclassification adjustment of realized capital gains and losses	5	62	27	121
Unrealized net capital gains and losses	(39)	162	(294)	375
Unrealized foreign currency translation adjustments	1	(2)	(1)	2
Other comprehensive income (loss)	(38)	160	(295)	377
After- tax
Unrealized net holding gains and losses arising during the period, net of related offsets	63	(62)	496	(230)
Less: reclassification adjustment of realized capital gains and losses	(10)	240	(51)	467
Unrealized net capital gains and losses	73	(302)	547	(697)
Unrealized foreign currency translation adjustments	(3)	3	1	(4)
Other comprehensive income (loss), after-tax	$ 70	$ (299)	$ 548	$ (701)