Investments (Details 28) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Assets on deposit:
Regulatory agencies	$ 1,950	$ 2,110
Assets held in trust:
Collateral financing arrangements	5,408	5,340
Reinsurance arrangements	2,971	3,090
Assets pledged as collateral:
Invested assets pledged as collateral	7,100	7,800
Total invested assets on deposit, held in trust and pledged as collateral	38,748	40,010
Federal Home Loan Bank of New York [Member]
Assets pledged as collateral:
Invested assets pledged as collateral	20,589	21,975
Federal Home Loan Bank of Boston [Member]
Assets pledged as collateral:
Invested assets pledged as collateral	534	211
Federal Home Loan Bank of Des Moines [Member]
Assets pledged as collateral:
Invested assets pledged as collateral	850	0
Funding agreements - Federal Agricultural Mortgage Corporation [Member]
Assets pledged as collateral:
Invested assets pledged as collateral	3,160	3,159
Federal Reserve Bank of New York [Member]
Assets pledged as collateral:
Invested assets pledged as collateral	1,654	1,822
Collateral financing arrangements [Member]
Assets pledged as collateral:
Invested assets pledged as collateral	93	112
Derivative transactions [Member]
Assets pledged as collateral:
Invested assets pledged as collateral	971	1,726
Short sale agreements [Member]
Assets pledged as collateral:
Invested assets pledged as collateral	$ 568	$ 465

Assets On Deposit Abstract.

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The sum of the fair values, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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Assets Pledged As Collateral Abstract.

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The fair value, as of the date of each statement of financial position presented, of other invested assets which are owned but transferred to serve as collateral for the payment of the related debt obligation, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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This item represents description of the terms and arrangement, as well as the amount of cash, securities, or other assets held by a third-party trustee pursuant to the terms of an agreement which assets are available to be used by beneficiaries to that agreement only within the specific terms thereof and which agreement is expected to terminate within one year of the balance sheet date (or operating cycle, if longer) at which time the assets held-in-trust will be released or forfeited.

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The fair value, as of the date of each statement of financial position presented, of other assets which are owned but transferred to serve as collateral for the payment of the related debt obligation, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 15
-Subparagraph a

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The fair value, as of the date of each statement of financial position presented, of securities which are owned but transferred to serve as collateral for the payment of the FHLB debt obligations, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 15
-Subparagraph a

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The fair value, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of other debt obligations, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 15
-Subparagraph a

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 71
-Paragraph 9, 10

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