Deferred Policy Acquisition Costs, Value of Business Acquired and Other Policy-Related Intangibles (DAC and VOBA) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deferred Policy Acquisition Costs and Value of Business Acquired [Abstract]
Beginning Balance of DAC	$ 6,338us-gaap_DeferredPolicyAcquisitionCosts	$ 5,752us-gaap_DeferredPolicyAcquisitionCosts	$ 6,244us-gaap_DeferredPolicyAcquisitionCosts
Beginning Balance of VOBA	78us-gaap_ValueOfBusinessAcquiredVOBA	80us-gaap_ValueOfBusinessAcquiredVOBA	97us-gaap_ValueOfBusinessAcquiredVOBA
Capitalizations of DAC	424	562	632
Net investment gains (losses) of DAC and net derivative gains (losses) of DAC	(104)	227	(270)
Other expenses of DAC	(583)	(478)	(709)
Other expenses of VOBA	(8)	(10)	(12)
Other	0	(220)	0
Total amortization of DAC	(687)	(251)	(979)
Total amortization of VOBA	(8)	(10)	(12)
Unrealized investment gains (losses) of DAC	(170)	495	(145)
Unrealized investment gains (losses) of VOBA	0	8	(5)
Ending Balance of DAC	5,905us-gaap_DeferredPolicyAcquisitionCosts	6,338us-gaap_DeferredPolicyAcquisitionCosts	5,752us-gaap_DeferredPolicyAcquisitionCosts
Ending Balance of VOBA	70us-gaap_ValueOfBusinessAcquiredVOBA	78us-gaap_ValueOfBusinessAcquiredVOBA	80us-gaap_ValueOfBusinessAcquiredVOBA
Balance at December 31	$ 5,975	$ 6,416	$ 5,832

Amount of amortization of present value of future insurance profits related to other expenses.

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Amount of expense related to deferred policy acquisition costs.

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Amount of amortization of deferred policy acquisition costs due to realized investment gains or losses.

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Amount of other increase (decrease) to amortization expense of deferred policy acquisition cost (DAC).

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Amount of increase (decrease) in deferred policy acquisition cost (DAC) due to unrealized investment gain (loss).

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Amount of increase (decrease) in deferred policy acquisition cost (DAC) due to the effect of foreign currency translation and other increase (decrease).

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Net amount of deferred policy acquisition costs capitalized on contracts remaining in force as of the balance sheet date.

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Total amount of policy acquisition costs capitalized during the income statement period.

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Carrying (unamortized) amount as of the balance sheet date of deferred policy acquisition costs and value of business acquired (also called present value of future profits).

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Amount of adjustment to reflect the effect that would have been recognized had the unrealized holding gain (loss) actually been realized on the present value of future insurance profits being amortized using the gross profit method and the present value of future profits recognized as a result of a purchase of an insurance entity holding long-duration contracts.

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Amount of the present value of future profits asset amortized.

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The remaining unamortized carrying amount as of the balance sheet date of expected future earnings from insurance contracts acquired (also known as present value of future profits).

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