Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Consolidated Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 1,150us-gaap_NetIncomeLoss	$ 361us-gaap_NetIncomeLoss	$ 1,196us-gaap_NetIncomeLoss
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax [Abstract]
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax	415	(159)	331
Other Comprehensive Income (Loss), Reclassification Adjustment to Net Income for Sale of Securities, Net of Tax	167	186	141
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent	248	(345)	190
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax [Abstract]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	(17)	(80)	184
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax	20	429	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	(37)	(509)	184
Other Comprehensive Income Unrealized Gain Loss On Net Investment Hedges Arising During the Period Net of Tax	8	37	(169)
Other Comprehensive Income (Loss), Reclassification Adjustment for Net Investment Hedges Included in Net Income, Discontinued Operation, Net of Tax	0	(169)	(1)
Other Comprehensive Income (Loss), Net Investment Hedges Attributable to Parent, Net of Tax	8	206	(168)
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustments and Net Investment Hedges, Adjustment, Net of Tax	(29)	(303)	16
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax [Abstract]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	2	(1)	(4)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	0	(4)	0
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	2	3	(4)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax [Abstract]
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax	(15)	18	(36)
Other Comprehensive Income (Loss), Reclassification Adjustment to Net Income, Pension and Other Postretirement Benefit Plans, for Net (Gain) Loss, Net of Tax	(4)	(40)	(58)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax, Portion Attributable to Parent	(11)	58	22
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	210	(587)	224
Comprehensive income (loss)	$ 1,360us-gaap_ComprehensiveIncomeNetOfTax	$ (226)us-gaap_ComprehensiveIncomeNetOfTax	$ 1,420us-gaap_ComprehensiveIncomeNetOfTax

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