Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2011
Net income	$ 677us-gaap_ProfitLoss	$ 471us-gaap_ProfitLoss	$ 556us-gaap_ProfitLoss
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(24)	(990)
Other Comprehensive Income (Loss), Net of Tax	647	(1,413)	1,034
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	1,324	(942)	1,590
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	1	6	2
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	1,323us-gaap_ComprehensiveIncomeNetOfTax	(948)us-gaap_ComprehensiveIncomeNetOfTax	1,588us-gaap_ComprehensiveIncomeNetOfTax
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(1)	(905)
Other Comprehensive Income (Loss), Net of Tax	659	(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	(23)	(85)
Other Comprehensive Income (Loss), Net of Tax	(9)	(179)
Accumulated Translation Adjustment [Member]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
Other Comprehensive Income (Loss), Net of Tax	$ (3)	$ 23

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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