Investments (Details 8) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Fair Value
Fixed income securities	$ 77,926	$ 76,113
Equity securities	3,681	4,363
Short-term Investments	1,867	1,291
Derivative instruments	(11)	(12)
Gross unrealized Gains
Fixed income securities	5,129	4,404
Equity securities	361	369
Derivative instruments		3
Gross unrealized Losses
Fixed income securities	(1,128)	(1,670)
Equity securities	(110)	(209)
Derivative instruments	(16)	(20)
Unrealized net gains (losses)
Fixed income securities	4,001	2,734
Equity securities	251	160
Derivative instruments	(16)	(17)
EMA limited partnerships	4	2
Unrealized net capital gains and losses, pre-tax	4,240	2,879
Amount recognized for:
Insurance reserves	(700)	(594)
DAC and DSI	(352)	(124)
Amounts recognized	(1,052)	(718)
Deferred income taxes	(1,118)	(761)
Total unrealized net capital gains and losses	2,070	1,400
Fair value of derivative securities classified as assets, with unrealized net gains (losses) in AOCI	(6)	(5)
Fair value of derivative securities classified as liabilities, with unrealized net gains (losses) in AOCI	$ 5	$ 7

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

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