Investments (Details 26) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
The Components of Net Investment Income
Fixed maturity securities	$ 3,791	$ 3,013	$ 7,474	$ 6,066
Equity securities	48	39	78	64
Trading securities - actively traded and FVO general account securities	16	(4)	44	11
Mortgage loans	766	695	1,525	1,368
Policy loans	160	157	320	333
Real estate and real estate joint ventures	200	135	354	179
Other limited partnership interests	159	161	402	426
Cash, cash equivalents and short-term investments	44	20	90	38
International joint ventures	9	(97)	(10)	(80)
Other	101	102	69	188
Subtotal	5,294	4,221	10,346	8,593
Less: Investment expenses	260	217	511	442
Subtotal, net	5,034	4,004	9,835	8,151
Trading securities - FVO contractholder-directed unit-linked investments	(32)	(52)	387	12
FVO consolidated securitization entities:
Commercial mortgage loans	96	105	191	210
Securities	0	4	1	8
Subtotal	64	57	579	230
Net investment income	5,098	4,061	10,414	8,381
Actively traded securities and FVO general account securities [Member]
Changes in estimated fair value subsequent to purchase included in net investment income:
Changes in estimated fair value included in net investment income	0	(19)	21	(15)
FVO contractholder-directed unit-linked investments [Member]
Changes in estimated fair value subsequent to purchase included in net investment income:
Changes in estimated fair value included in net investment income	$ (84)	$ (71)	$ 232	$ (14)

Changes in estimated fair value subsequent to purchase included in net investment income.

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The Components of Net Investment Income Abstract.

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FVO consolidated securitization entities.

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The amount of equity method investment earnings on the investment in a non-consolidated joint ventures.

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The amount of investment earnings, excluding realized and unrealized gain (loss), recognized in the period on commercial mortgage loans held by consolidated securitization entities, net of related investment expenses.

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Subtotal of securities and loans held by consolidated securitization entities.

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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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The amount of investment earnings, excluding realized and unrealized gain (loss), recognized in the period on other components of net investment income, net of related investment expenses.

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The amount of investment earnings, excluding realized and unrealized gain (loss), recognized in the period on other limited partnership interests, net of related investment expenses.

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Reflects net investment income (the sum of all other revenue and income recognized by the entity less related expenses).

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Reflects the total sum of all other revenue and income recognized by the entity in the period not otherwise specified in the income statement.

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The amount of investment earnings, including realized gain (loss), recognized in the period on trading securities - FVO contractholder-directed unit-linked investments.

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Total expenses related to the generation of investment income in debt and equity securities.

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The income earned from investments in securities and property, equipment and other capital assets. It includes rent from property and equipment, dividends from shares in corporations, and interest from bonds, loans, mortgages, derivatives, commercial paper, bank accounts, certificates of deposits, treasuries, and other financial securities. It does not include realized gains and losses on investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 16
-Article 12

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

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The amount of investment earnings, excluding realized and unrealized gain (loss), recognized in the period on holdings of equity securities, net of related investment expenses.

+ References