Investments (Details 9) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fair value
Fixed income securities:	$ 61,403	$ 62,440
Equity securities	4,166	4,104
Short-term investments	2,497us-gaap_ShortTermInvestments	2,540us-gaap_ShortTermInvestments
Derivative instruments	7	2
Gross unrealized Gains
Fixed income securities	3,405	3,082
Equity securities	468	467
Short-term investments	0	0
Derivative instruments	8	3
Gross unrealized Losses
Fixed income securities	(237)	(314)
Equity securities	(54)	(55)
Short-term investments	0	0
Derivative instruments	(5)	(5)
Unrealized net gains (losses)
Fixed income securities	3,168	2,768
Equity securities	414	412
Short-term investments	0	0
Derivative instruments	3	(2)
EMA limited partnerships	(4)	(5)
Unrealized net capital gains and losses, pre-tax	3,581	3,173
Amount recognized for:
Insurance reserves	(79)	(28)
DAC and DSI	(212)	(179)
Amounts recognized	(291)	(207)
Deferred income taxes	(1,153)	(1,040)
Total unrealized net capital gains and losses	2,137	1,926
Fair value of derivative securities classified as assets, with unrealized net gains (losses) in AOCI	7	3
Fair value of derivative securities classified as liabilities, with unrealized net gains (losses) in AOCI	$ 0	$ 1

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Available for sale Short-term Investments, Unrealized Gain Included in Other Comprehensive Income

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Accumulated adjustment to deferred income taxes related to unrealized capital gains and losses, as of the balance sheet date.

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Accumulated adjustment to Deferred Policy Acquisition Costs, Deferred Sales Inducement Costs, and insurance reserves related to unrealized capital gains and losses, before tax, at the end of an accounting period.

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Deferred Policy Acquisition Costs and Deferred Sales Inducement Costs adjustment included in accumulated other comprehensive income (loss) which represents the amount by which the amortization of DAC and DSI would increase or decrease if the unrealized gains or losses in the respective product portfolios were realized.

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The amount of unrealized gains included in accumulated other comprehensive income on derivative instruments, as of the balance sheet date.

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Fair value as of the balance sheet date of the assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, for which an unrealized net gain or loss is included in accumulated other comprehensive income.

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Fair value as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, for which an unrealized net gain or loss is included in accumulated other comprehensive income.

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Fair value as of the balance sheet date of the liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, for which an unrealized net gain or loss is included in accumulated other comprehensive income.

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Insurance reserve adjustment included in accumulated other comprehensive income (loss) which represents the amount by which the reserve balance would increase if the net unrealized gains in the applicable product portfolios were realized and reinvested at current lower interest rates, resulting in a premium deficiency.

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The amount of unrealized gain (loss) before taxes on all investment securities, which are included in accumulated other comprehensive income (loss), as a result of fair value exceeding (under) its cost, as of the balance sheet date.

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Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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