Fair Value Measurements Level 4 Fair Value by Hierarchy (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount	$ 0
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	59,384,000,000	62,357,000,000
Marketable Securities, Fixed Maturities	488,000,000	844,000,000
Trading Securities, Equity	11,000,000	19,745,000,000
Available-for-sale Securities, Equity Securities	1,047,000,000	868,000,000
Other Short-term Investments	4,883,000,000	4,008,000,000
Alternative Investments, Fair Value Disclosure	2,942,000,000	3,040,000,000
Reinsurance Recoverables	22,920,000,000	23,330,000,000
Separate Account Assets	134,702,000,000	140,886,000,000
Assets, Fair Value Disclosure	199,248,000,000	227,776,000,000
Liabilities, Fair Value Disclosure [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	(1,095,000,000)
Derivative Liability, Fair Value, Amount Offset Against Collateral	137,000,000	74,000,000
Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	106,000,000	1,311,000,000
Marketable Securities, Fixed Maturities	0	0
Trading Securities, Equity	11,000,000	12,000,000
Available-for-sale Securities, Equity Securities	786,000,000	454,000,000
Other Short-term Investments	349,000,000	427,000,000
Assets, Fair Value Disclosure	92,789,000,000	102,134,000,000
Liabilities, Fair Value Disclosure [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0
Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	55,803,000,000	56,892,000,000
Marketable Securities, Fixed Maturities	396,000,000	651,000,000
Trading Securities, Equity	0	19,733,000,000
Available-for-sale Securities, Equity Securities	163,000,000	337,000,000
Other Short-term Investments	4,534,000,000	3,581,000,000
Assets, Fair Value Disclosure	101,735,000,000	120,072,000,000
Liabilities, Fair Value Disclosure [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	(1,004,000,000)
Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	3,475,000,000	4,154,000,000
Marketable Securities, Fixed Maturities	92,000,000	193,000,000
Trading Securities, Equity	0	0
Available-for-sale Securities, Equity Securities	98,000,000	77,000,000
Other Short-term Investments	0	0
Assets, Fair Value Disclosure	4,724,000,000	5,570,000,000
Liabilities, Fair Value Disclosure [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	(91,000,000)
Fair Value, Measurements, Recurring [Member]
Liabilities, Fair Value Disclosure [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure		(1,273,000,000)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Liabilities, Fair Value Disclosure [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure		0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Liabilities, Fair Value Disclosure [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure		(1,247,000,000)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Liabilities, Fair Value Disclosure [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure		(26,000,000)
Asset-backed Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	2,472,000,000	2,365,000,000
Asset-backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Asset-backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	2,350,000,000	2,218,000,000
Asset-backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	122,000,000	147,000,000
Collateralized Debt Obligations [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	2,841,000,000	2,387,000,000
Collateralized Debt Obligations [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Collateralized Debt Obligations [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	2,218,000,000	1,723,000,000
Collateralized Debt Obligations [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	623,000,000	664,000,000
Commercial Mortgage Backed Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	4,415,000,000	4,446,000,000
Commercial Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Commercial Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	4,131,000,000	3,783,000,000
Commercial Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	284,000,000	663,000,000
Commercial Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	284,000,000	663,000,000
Corporate Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	27,359,000,000	28,490,000,000
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	26,319,000,000	27,216,000,000
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	1,040,000,000	1,274,000,000
Foreign Government Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	1,636,000,000	4,104,000,000
Foreign Government Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Foreign Government Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	1,577,000,000	4,039,000,000
Foreign Government Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	59,000,000	65,000,000
US States and Political Subdivisions Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	12,871,000,000	12,173,000,000
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	0	0
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	12,805,000,000	12,104,000,000
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	66,000,000	69,000,000
Residential Mortgage Backed Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	3,918,000,000	4,647,000,000
Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	2,637,000,000	3,375,000,000
Residential Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	1,281,000,000	1,272,000,000
Residential Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	1,281,000,000	1,272,000,000
US Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	2,500,000,000	1,300,000,000
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	3,872,000,000	3,745,000,000
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	106,000,000	1,311,000,000
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	3,766,000,000	2,434,000,000
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Debt Securities	0	0
Other Policyholder Funds and Benefits Payable [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(165,000,000)
Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(165,000,000)
Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(48,000,000)
Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(48,000,000)
Credit Risk Contract [Member] | Other Investments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	8,000,000	25,000,000
Credit Risk Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Credit Risk Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	10,000,000	20,000,000
Credit Risk Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(2,000,000)	5,000,000
Credit Risk Contract [Member] | Other Liabilities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(16,000,000)
Credit Risk Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Credit Risk Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(9,000,000)
Credit Risk Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(7,000,000)
Credit Risk Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(12,000,000)
Credit Risk Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Credit Risk Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(9,000,000)
Credit Risk Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(3,000,000)
Equity Contract [Member] | Other Investments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	3,000,000
Equity Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Equity Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Equity Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	3,000,000
Equity Contract [Member] | Other Liabilities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	28,000,000
Equity Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Equity Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	25,000,000
Equity Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	3,000,000
Equity Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		19,000,000
Equity Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Equity Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		16,000,000
Equity Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		3,000,000
Foreign Exchange Contract [Member] | Other Investments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		14,000,000
Foreign Exchange Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Foreign Exchange Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		14,000,000
Foreign Exchange Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Foreign Exchange Contract [Member] | Other Liabilities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(445,000,000)
Foreign Exchange Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Foreign Exchange Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(445,000,000)
Foreign Exchange Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Foreign Exchange Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(388,000,000)
Foreign Exchange Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Foreign Exchange Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(388,000,000)
Foreign Exchange Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Interest Rate Contract [Member] | Other Investments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	129,000,000	(21,000,000)
Interest Rate Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Interest Rate Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	113,000,000	(63,000,000)
Interest Rate Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	16,000,000	42,000,000
Interest Rate Contract [Member] | Other Liabilities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(597,000,000)
Interest Rate Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Interest Rate Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(574,000,000)
Interest Rate Contract [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(23,000,000)
Interest Rate Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(582,000,000)
Interest Rate Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Interest Rate Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(558,000,000)
Interest Rate Contract [Member] | Other Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(24,000,000)
Other Contract [Member] | Other Investments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	12,000,000	17,000,000
Other Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Other Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Other Contract [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	12,000,000	17,000,000
Derivative Financial Instruments, Assets [Member] | Other Investments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	364,000,000	442,000,000
Derivative Financial Instruments, Assets [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	128,000,000	170,000,000
Derivative Financial Instruments, Assets [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	236,000,000	272,000,000
Derivative Financial Instruments, Liabilities [Member]
Liabilities, Fair Value Disclosure [Abstract]
Derivative Liability, Fair Value, Amount Offset Against Collateral	413,000,000	128,000,000
Derivative Financial Instruments, Liabilities [Member] | Other Liabilities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(927,000,000)	(1,223,000,000)
Derivative Financial Instruments, Liabilities [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Derivative Financial Instruments, Liabilities [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(1,004,000,000)	(1,247,000,000)
Derivative Financial Instruments, Liabilities [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	77,000,000	24,000,000
Embedded Derivative Financial Instruments [Member] | Other Liabilities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(3,000,000)	(2,000,000)
Embedded Derivative Financial Instruments [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Embedded Derivative Financial Instruments [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
Embedded Derivative Financial Instruments [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(3,000,000)	(2,000,000)
GMWB Reinsurance [Member]
Assets, Fair Value Disclosure [Abstract]
Reinsurance Recoverables	56,000,000	29,000,000
GMWB Reinsurance [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Reinsurance Recoverables	0	0
GMWB Reinsurance [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Reinsurance Recoverables	0	0
GMWB Reinsurance [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Reinsurance Recoverables	56,000,000	29,000,000
Coinsurance and Modified Coinsurance Reinsurance Contracts [Member]
Assets, Fair Value Disclosure [Abstract]
Reinsurance Recoverables	34,000,000	67,000,000
Coinsurance and Modified Coinsurance Reinsurance Contracts [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Reinsurance Recoverables	0	0
Coinsurance and Modified Coinsurance Reinsurance Contracts [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Reinsurance Recoverables	34,000,000	67,000,000
Coinsurance and Modified Coinsurance Reinsurance Contracts [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Reinsurance Recoverables	0	0
Equity Linked Notes [Member] | Other Policyholder Funds and Benefits Payable [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(26,000,000)
Equity Linked Notes [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Equity Linked Notes [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Equity Linked Notes [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(26,000,000)
Equity Linked Notes [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(18,000,000)
Equity Linked Notes [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Equity Linked Notes [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Equity Linked Notes [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(18,000,000)
UNITED STATES | US GMWB Hedging Instruments [Member] | Other Investments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	119,000,000	26,000,000
UNITED STATES | US GMWB Hedging Instruments [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
UNITED STATES | US GMWB Hedging Instruments [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	5,000,000	(42,000,000)
UNITED STATES | US GMWB Hedging Instruments [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	114,000,000	68,000,000
UNITED STATES | US GMWB Hedging Instruments [Member] | Other Liabilities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	55,000,000	15,000,000
UNITED STATES | US GMWB Hedging Instruments [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
UNITED STATES | US GMWB Hedging Instruments [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(1,000,000)	(63,000,000)
UNITED STATES | US GMWB Hedging Instruments [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	56,000,000	78,000,000
UNITED STATES | Macro Hedge Program [Member] | Other Investments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	93,000,000	109,000,000
UNITED STATES | Macro Hedge Program [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
UNITED STATES | Macro Hedge Program [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
UNITED STATES | Macro Hedge Program [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	93,000,000	109,000,000
UNITED STATES | Macro Hedge Program [Member] | Other Liabilities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	48,000,000	30,000,000
UNITED STATES | Macro Hedge Program [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
UNITED STATES | Macro Hedge Program [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0	0
UNITED STATES | Macro Hedge Program [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	48,000,000	30,000,000
JAPAN | International Program Hedging Instruments [Member] | Other Investments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		272,000,000
JAPAN | International Program Hedging Instruments [Member] | Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
JAPAN | International Program Hedging Instruments [Member] | Other Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		241,000,000
JAPAN | International Program Hedging Instruments [Member] | Other Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		31,000,000
JAPAN | International Program Hedging Instruments [Member] | Other Liabilities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(305,000,000)
JAPAN | International Program Hedging Instruments [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
JAPAN | International Program Hedging Instruments [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(245,000,000)
JAPAN | International Program Hedging Instruments [Member] | Other Liabilities [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(60,000,000)
Portion at Other than Fair Value Measurement [Member]
Assets, Fair Value Disclosure [Abstract]
Separate Account Assets	2,500,000,000	2,400,000,000
Portion at Fair Value Measurement [Member]
Assets, Fair Value Disclosure [Abstract]
Alternative Investments, Fair Value Disclosure	770,000,000	921,000,000
Separate Account Assets	132,211,000,000	138,495,000,000
Portion at Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Alternative Investments, Fair Value Disclosure	0	0
Separate Account Assets	91,537,000,000	99,930,000,000
Portion at Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Alternative Investments, Fair Value Disclosure	581,000,000	813,000,000
Separate Account Assets	40,096,000,000	37,828,000,000
Portion at Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Alternative Investments, Fair Value Disclosure	189,000,000	108,000,000
Separate Account Assets	578,000,000	737,000,000
Guaranteed Minimum Withdrawal Benefit [Member] | UNITED STATES | Other Policyholder Funds and Benefits Payable [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(139,000,000)
Guaranteed Minimum Withdrawal Benefit [Member] | UNITED STATES | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Guaranteed Minimum Withdrawal Benefit [Member] | UNITED STATES | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	0
Guaranteed Minimum Withdrawal Benefit [Member] | UNITED STATES | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net	(139,000,000)
Guaranteed Minimum Withdrawal Benefit [Member] | UNITED STATES | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(36,000,000)
Guaranteed Minimum Withdrawal Benefit [Member] | UNITED STATES | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Guaranteed Minimum Withdrawal Benefit [Member] | UNITED STATES | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Guaranteed Minimum Withdrawal Benefit [Member] | UNITED STATES | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		(36,000,000)
Guaranteed Minimum Withdrawal Benefit [Member] | International [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		3,000,000
Guaranteed Minimum Withdrawal Benefit [Member] | International [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Guaranteed Minimum Withdrawal Benefit [Member] | International [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Guaranteed Minimum Withdrawal Benefit [Member] | International [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		3,000,000
Other Guaranteed Living Benefits [Member] | International [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		3,000,000
Other Guaranteed Living Benefits [Member] | International [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Other Guaranteed Living Benefits [Member] | International [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		0
Other Guaranteed Living Benefits [Member] | International [Member] | Other Policyholder Funds and Benefits Payable [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets (Liabilities), at Fair Value, Net		$ 3,000,000