Investments (Details 21) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Net investment gains (losses)	$ (175)	$ (53)	$ (302)	$ (92)
Total gains (losses) on fixed maturity securities:
Other-than-temporary impairments on fixed maturity securities	(298)	(244)	(430)	(395)
Less: Noncredit portion of OTTI gains (losses) transferred to and recognized in other comprehensive income (loss)	175	98	184	157
Total OTTI losses recognized in earnings	(123)	(146)	(246)	(238)
Fixed maturity securities - net gains (losses) on sales and disposals	18	19	(22)	45
Other net investment gains (losses):
Mortgage Loans	68	11	115	(17)
Real estate and real estate joint ventures	4	(27)	5	(49)
Other limited partnership interests	5	(10)	8	(11)
Other investment portfolio gains (losses)	(6)	17	(2)	76
Subtotal - investment portfolio gains (losses)	(104)	(62)	(176)	(93)
FVO consolidated securitization entities - changes in estimated fair value included in net investment gains (losses):
Commercial mortgage loans	7	172	25	653
Trading securities	39	(17)	(1)	(21)
Long-term debt - related to trading securities	(54)	(1)	(7)	11
Long-term debt - related to commercial mortgage loans	(8)	(156)	(8)	(635)
Other Gains Losses	(35)	50	(87)	103
Subtotal consolidated securitizations entities and other gains (losses)	(51)	48	(78)	111
Total net investment gains (losses)	(155)	(14)	(254)	18
Fixed maturity securities [Member]
Net investment gains (losses)	(105)	(127)	(268)	(193)
Total gains (losses) on fixed maturity securities:
Total OTTI losses recognized in earnings	(123)	(146)	(246)	(238)
Equity Securities [Member]
Net investment gains (losses)	$ (70)	$ 74	$ (34)	$ 101

Consolidated securitization entities.

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Debt Securities Other Than Temporary Impairment Losses Recognized In Earnings Net.

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Fixed Maturity Realized Gains Losses Abstract.

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This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity. Additionally, this item would include any losses recognized for other than temporary impairments of the subject investments in debt securities.

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The net gain or loss incurred on assets and liabilities held by consolidated securitizations entities and all other gains and losses.

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The net gain or loss resulting from the change in fair value of commercial mortgage loans held by consolidated securitization entities not required to be reported separately in the statement of income for which the Company has elected the fair value option.

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The net gain or loss resulting from the sale or disposal of long-term debt relating to mortgage loans of consolidated securitization entities not required to be reported separately in the statement of income for which the Company has elected the fair option.

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The net change during the reporting period in the aggregate market value of equity or debt securities held by consolidated securitization entities that are purchased and held principally for the purpose of selling them in the near future.

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This item represents the subtotal of gains (losses)on the investment portfolio.

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The net gain or loss resulting from sales and other disposals and increases and decreases to their valuation.

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The net gain or loss resulting from sales and other disposals of other limited partnership interests.

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The net gain or loss incurred on investments held outside of the investment portfolio and all other gains and losses reported in net investment gains (losses).

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The net gain or loss resulting from the sale or disposal of all other investments.

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This element represents the amount of loss recognized for other-than-temporary impairments of investments in debt securities.

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Other-than-temporary impairments of fixed maturity securities transferred to other comprehensive income (loss).

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain or loss of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain or loss which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains or losses realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments of the subject investments.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 22

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The net gain or loss resulting from sales and other disposals of real estate owned for investment purposes.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher OTS
-Name Federal Regulation (FR)
-Number Title 12
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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The net realized gains or losses on investments during the period.

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