Accumulated Other Comprehensive Income Level 4 (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 7,821				$ 8,162				$ 7,821	$ 8,162	$ 9,291	$ 8,239
Accumulated Other Comprehensive Income (Loss), Net of Tax	722				593				722	593	1,221	574
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax									203	(631)	671
Gain (Loss) on Investments, Excluding Other than Temporary Impairments									(135)	(85)	606
Income Tax Expense (Benefit)									74	30	184
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax									(74)	3	(24)
Other Comprehensive Income (Loss), Net of Tax									129	(628)	647
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	57	$ 79	$ 118	$ 28	7	$ 118	$ 230	$ 145	282	500	677
Cash Flow Hedging [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net									24	23
Investment Income [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net										33	50
Gain (Loss) on Investments [Member] | Currency Swap [Member] | Cash Flow Hedging [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net										(9)	(13)
Gain (Loss) on Investments [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net										(1)	(1)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax									74	(3)	24
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Unrealized Investment Gain (Loss) [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net									1
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Currency Swap [Member] | Cash Flow Hedging [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net									(2)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Interest Income [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net									25
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	693				539				693	539	1,154
Accumulated Other Comprehensive Income (Loss), Net of Tax											1,154	495
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax									212	(633)	660
Gain (Loss) on Investments, Excluding Other than Temporary Impairments									89	(27)	1
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest										(27)
Income Tax Expense (Benefit)									31	(9)	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax									(58)	18	(1)
Other Comprehensive Income (Loss), Net of Tax											659
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax									154	(615)
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Gain (Loss) on Investments, Excluding Other than Temporary Impairments									0	0	0
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest									89		1
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax									58	(18)	1
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	32				57				32	57	70
Accumulated Other Comprehensive Income (Loss), Net of Tax											70	79
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax									(9)	2	14
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax									(16)	(15)	(23)
Other Comprehensive Income (Loss), Net of Tax											(9)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax									(25)	(13)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income Tax Expense (Benefit)									8	8	13
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Cash Flow Hedging [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest									24	23	36
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax									16	15	23
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(3)				(3)				(3)	(3)	(3)
Accumulated Other Comprehensive Income (Loss), Net of Tax											(3)	0
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax									0	0	(3)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax									0	0	0
Other Comprehensive Income (Loss), Net of Tax											(3)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax									0	0
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 722				$ 593				$ 722	593	1,221	$ 574
Other Comprehensive Income (Loss), Net of Tax										$ (628)	$ 647