Derivatives (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Derivatives, Fair Value [Line Items]
Estimated Fair Value Assets	$ 10,171,000,000		$ 10,171,000,000		$ 8,595,000,000
Estimated Fair Value Liabilities	5,166,000,000		5,166,000,000		6,521,000,000
Maximum Amount of Future Payments under Credit Default Swaps	10,929,000,000		10,929,000,000		9,055,000,000
Estimated Fair Value of Credit Default Swaps	147,000,000		147,000,000		165,000,000
Excess securities collateral received on derivatives	158,000,000		158,000,000		104,000,000
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Average Remaining Maturity			3 years 3 months		3 years 5 months
Embedded derivatives	(65,000,000)	898,000,000	55,000,000	3,661,000,000
Gain (Loss) on Investments	(109,000,000)	85,000,000	427,000,000	(339,000,000)
Derivative Instrument Detail [Abstract]
Net amounts reclassified into net derivatives gains (losses) on discontinued cash flow hedges	(11,000,000)	0	(15,000,000)	0
Hedging exposure to variability in future cash flows for specific length of time			7 years		7 years
Accumulated Other Comprehensive Income Loss	1,300,000,000		1,300,000,000		375,000,000
Deferred net gains (losses) expected to be reclassified to earnings			106,000,000
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)		0		0
Immateriality of cash flow effectiveness	0	0	0	0
Cumulative foreign currency translation gain (loss) recorded in accumulated other comprehensive income (loss) for net investment in foreign operations hedges	383,000,000		383,000,000		233,000,000
Potential future recoveries available to offset maximum amount of future payments under credit default swaps	75,000,000		75,000,000		90,000,000
Excess securities collateral provided on derivatives	159,000,000		159,000,000		236,000,000
Change in fair value of derivatives excluded from the assessment of hedge effectiveness	(2,000,000)	0	3,000,000	0
Securities collateral received which the company is permitted to sell or repledge, amount that has been sold or repledged	0		0
Ba [Member]
Derivatives, Fair Value [Line Items]
Maximum Amount of Future Payments under Credit Default Swaps	155,000,000		155,000,000		5,000,000
Estimated Fair Value of Credit Default Swaps	0		0		0
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Average Remaining Maturity			2 years 8 months		3 years 9 months
Nonperformance Risk [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Embedded derivatives	5,000,000	(145,000,000)	(3,000,000)	(795,000,000)
B [Member]
Derivatives, Fair Value [Line Items]
Maximum Amount of Future Payments under Credit Default Swaps	501,000,000		501,000,000		375,000,000
Estimated Fair Value of Credit Default Swaps	23,000,000		23,000,000		32,000,000
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Average Remaining Maturity			4 years 1 month		4 years 11 months
Accumulated Other Comprehensive Income (Loss) Foreign Currency Translation Adjustments [Member] | MetLife Assurance Limited [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Investments	0		77,000,000
Over the Counter [Member]
Derivatives, Fair Value [Line Items]
Cash collateral on derivative assets	(2,797,000,000)		(2,797,000,000)		(1,679,000,000)
Excess securities collateral received on derivatives	260,000,000		260,000,000		238,000,000
Excess securities collateral provided on derivatives	51,000,000		51,000,000		66,000,000
Exchange Traded [Member]
Derivatives, Fair Value [Line Items]
Cash collateral on derivative assets	0		0		0
Excess securities collateral received on derivatives	131,000,000		131,000,000		141,000,000
Excess securities collateral provided on derivatives	220,000,000		220,000,000		81,000,000
Hedge Funds [Member]
Derivatives, Fair Value [Line Items]
Maximum Amount of Future Payments under Credit Default Swaps	45,000,000		45,000,000		10,000,000
Estimated Fair Value of Credit Default Swaps	2,000,000		2,000,000		0
Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value Assets	181,000,000		181,000,000		255,000,000
Estimated Fair Value Liabilities	37,000,000		37,000,000		28,000,000
Off-Balance Sheet [Member]
Derivatives, Fair Value [Line Items]
Excess securities collateral received on derivatives	113,000,000		113,000,000
Off-Balance Sheet [Member] | Over the Counter [Member]
Derivatives, Fair Value [Line Items]
Cash collateral on derivative assets	(249,000,000)		(249,000,000)		0
Credit Index Product [Member] | Ba [Member]
Derivatives, Fair Value [Line Items]
Maximum Amount of Future Payments under Credit Default Swaps	100,000,000		100,000,000		0
Estimated Fair Value of Credit Default Swaps	0		0		0
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Average Remaining Maturity			2 years 6 months		0 years
Credit Index Product [Member] | B [Member]
Derivatives, Fair Value [Line Items]
Maximum Amount of Future Payments under Credit Default Swaps	501,000,000		501,000,000		375,000,000
Estimated Fair Value of Credit Default Swaps	23,000,000		23,000,000		32,000,000
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Average Remaining Maturity			4 years 1 month		4 years 11 months
Credit Default Swap [Member] | Ba [Member]
Derivatives, Fair Value [Line Items]
Maximum Amount of Future Payments under Credit Default Swaps	55,000,000		55,000,000		5,000,000
Estimated Fair Value of Credit Default Swaps	0		0		0
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Average Remaining Maturity			3 years 0 months		3 years 9 months
Credit Default Swap [Member] | B [Member]
Derivatives, Fair Value [Line Items]
Maximum Amount of Future Payments under Credit Default Swaps	0		0		0
Estimated Fair Value of Credit Default Swaps	$ 0		$ 0		$ 0
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Average Remaining Maturity			0 years		0 years