Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net income	$ 500	$ 677	$ 471
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	3	(24)	(990)
Other Comprehensive Income (Loss), Net of Tax	(628)	647	(1,413)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(128)	1,324	(942)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0	1	6
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	(128)	1,323	(948)
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	(615)	659
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	18	(1)	(905)
Other Comprehensive Income (Loss), Net of Tax			(1,257)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(15)	(23)	(85)
Other Comprehensive Income (Loss), Net of Tax			(179)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	(13)	(9)
Accumulated Translation Adjustment [Member]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0	0
Other Comprehensive Income (Loss), Net of Tax			$ 23
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	$ 0	$ (3)