Investments (Details 5) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Investments.
Impairment write-downs	$ (70)	$ (239)	$ (184)	$ (462)
Change in intent write-downs	(16)	(67)	(85)	(99)
Net other-than-temporary impairment losses recognized in earnings	(86)	(306)	(269)	(561)
Sales	141	145	424	233
Valuation of derivative instruments	(50)	(283)	(28)	(438)
Settlements of derivative instruments	(3)	(27)	(92)	(57)
Equity method of accounting ("EMA") limited partnership income	55	20	118	24
Realized capital gains and losses	57	(451)	153	(799)
Gross gains on sales of fixed income securities	177	144	388	286
Gross loss on sales of fixed income securities	$ 98	$ 113	$ 186	$ 187

This item represents the gross profit realized on the sale of debt securities categorized neither as held-to-maturity nor trading securities.

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- Definition

This item represents the gross loss realized on the sale of debt securities categorized neither as held-to-maturity nor trading securities.

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- Definition

The amount of change in intent write-downs reflect instances where the Company has made a decision to sell the security or it is more likely than not the Company will be required to sell the security before recovery of its amortized cost basis.

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- Definition

The amount of other than temporary impairment losses on equity securities and other than temporary impairment related to credit losses on debt securities. Additionally, this item includes other than temporary impairment losses recognized during the period on investments accounted for under the cost method of accounting.

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- Details

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- Definition

The amount of other than temporary impairment losses on equity securities, other than temporary impairment related to credit losses on debt securities, and other than temporary impairment losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes other than temporary impairment losses recognized during the period on investments accounted for under the cost method of accounting.

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- Definition

Net increase (decrease) in the fair value of the derivative or group of derivatives included in earnings.

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- Definition

The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings .

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

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- Definition

The net gain or loss realized from the sale, exchange, redemption, or retirement of securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 13
-Subparagraph h
-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 3
-Article 7

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. Such amount typically reflects adjustments similar to those made in preparing consolidated statements, including adjustments to eliminate intercompany gains and losses, and to amortize, if appropriate, any difference between cost and underlying equity in net assets of the investee at the date of investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 19
-Subparagraph c

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 11
-Article 7

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 9
-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 6
-Subparagraph b

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- Definition

The net realized gains or losses on investments during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 3
-Subparagraph a
-Article 7

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