Investments (Details 22) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Components of Sales or Disposals of Fixed Maturity and Equity Securities
Proceeds	$ 15,863	$ 19,805	$ 35,382	$ 36,653
Gross investment gains	248	261	583	502
Gross investment losses	(154)	(266)	(490)	(505)
Total OTTI losses recognized in earnings:
Credit-related	(68)	(70)	(141)	(113)
Other	(25)	(100)	(100)	(186)
Total OTTI losses recognized in earnings	(91)	(123)	(224)	(246)
Total OTTI losses recognized in earnings	2	47	17	53
Total OTTI losses recognized in earnings	(93)	(170)	(241)	(299)
Net investment gains (losses)	1	(175)	(148)	(302)
Fixed maturity securities [Member]
Components of Sales or Disposals of Fixed Maturity and Equity Securities
Proceeds	15,625	19,316	35,019	35,848
Gross investment gains	225	235	550	428
Gross investment losses	(152)	(217)	(484)	(450)
Total OTTI losses recognized in earnings:
Credit-related	(68)	(70)	(141)	(113)
Other	(23)	(53)	(83)	(133)
Total OTTI losses recognized in earnings	(91)	(123)	(224)	(246)
Net investment gains (losses)	(18)	(105)	(158)	(268)
Equity Securities [Member]
Components of Sales or Disposals of Fixed Maturity and Equity Securities
Proceeds	238	489	363	805
Gross investment gains	23	26	33	74
Gross investment losses	(2)	(49)	(6)	(55)
Total OTTI losses recognized in earnings:
Credit-related	0	0	0	0
Other	(2)	(47)	(17)	(53)
Total OTTI losses recognized in earnings	(2)	(47)	(17)	(53)
Net investment gains (losses)	$ 19	$ (70)	$ 10	$ (34)

Credit-related OTTI gains (losses) recognized in earnings.

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This item represents the total equity security other than temporary impairment losses recognized in earnings, net.

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Other OTTI gains (losses) recognized in earnings.

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

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 21

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-Section 50

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities and excluding other than temporary impairments (OTTI), if any, recognized elsewhere.

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This element represents the amount of loss recognized for other than temporary impairments (OTTI) of investments in debt and equity securities.

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-Name Statement of Financial Accounting Standard (FAS)

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

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The cash inflow associated with the sale of insurance policy investment assets during the period.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 15, 16

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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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