Investments (Details 27) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Aging of cash collateral liability:
Open	$ 2,440	$ 2,752
Less than thirty days	14,993	12,301
Thirty days or greater but less than sixty days	5,405	4,399
Sixty days or greater but less than ninety days	2,057	2,291
Ninety Days Or Greater Aging Of Cash Collateral Liability Securities Lending	908	2,904
Total cash collateral liability	25,803	24,647
Security collateral on deposit from counterparties	613	0
Reinvestment portfolio - estimated fair value	25,520	24,177
Securities Financing Transaction, Cost [Member]
Securities Financing Transaction [Line Items]
Securities loaned	22,488	23,715
Securities Financing Transaction, Fair Value [Member]
Securities Financing Transaction [Line Items]
Securities loaned	$ 26,040	$ 24,230

Aging Of Cash Collateral Liability Abstract.

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The total cash collateral liability for securities loaned.

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This element represents the cash collateral liability amount related to loaned securities that could be returned to the Company over the next 2 - 29 business days from the stated date requiring the Company to immediately return the cash collateral.

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This element represents the cash collateral liability amount related to loaned securities that could be returned to the Company 90 business days or greater from the stated date requiring the Company to immediately return the cash collateral.

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This element represents the cash collateral liability amount related to loaned securities in the open category. Open means that the related loaned security could be returned to the Company on the next business day requiring the Company to immediately return the cash collateral.

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This element represents the estimated fair value of the securities lending reinvestment portfolio.

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This element represents the cash collateral liability amount related to loaned securities that could be returned to the Company over the next 60 - 89 business days from the stated date requiring the Company to immediately return the cash collateral.

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This element represents the cash collateral liability amount related to loaned securities that could be returned to the Company over the next 30 - 59 business days from the stated date requiring the Company to immediately return the cash collateral.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The carrying value as of the balance sheet date of securities loaned to other broker dealers, typically used by such parties to cover short sales, secured by cash or other securities furnished by such parties until the borrowing is closed.

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The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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