Supplemental Cash Flow Information (Details) (USD $) In Millions	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Supplemental Cash Flow Information
Non-cash investment exchanges, including modifications of certain mortgage loans (primarily refinances at maturity with no concessions granted to the borrower), fixed income securities, limited partnerships and other investments, as well as mergers completed with equity securities	$ 564	$ 544
Net change in proceeds managed
Net change in short-term investments	(301)	187
Operating cash flow (used) provided	(301)	187
Net change in cash	1	2
Net change in proceeds managed	(300)	189
Net change in liabilities
Liabilities for collateral, beginning of year	(484)	(658)
Liabilities for collateral, end of period	(784)	(469)
Operating cash flow provided (used)	$ 300	$ (189)

The net operating cash flow provided by (used in) the net change in liabilities for collateral.

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The net operating cash flow provided or used related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

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The net change in cash from the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

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The net change in the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

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The net change in short-term investments from the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

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The liability to return cash and securities received as collateral in conjunction with securities lending and over-the-counter derivatives.

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Value of investments transferred in noncash transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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