Investments (Net Investment Income) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
The Components of Net Investment Income
Fixed maturity securities	$ 3,709	$ 3,737	$ 7,535	$ 7,545
Equity securities	36	38	60	70
Trading securities - actively traded and FVO general account securities	(11)	(1)	10	44
Mortgage loans	716	764	1,454	1,594
Policy loans	152	156	307	314
Real estate and real estate joint ventures	243	280	436	457
Other limited partnership interests	275	266	521	448
Cash, cash equivalents and short-term investments	45	39	94	75
International joint ventures	5	1	(9)	4
Other	49	80	112	121
Subtotal	5,219	5,360	10,520	10,672
Less: Investment expenses	287	258	587	517
Subtotal, net	4,932	5,102	9,933	10,155
Trading securities - FVO contractholder-directed unit-linked investments	314	(517)	1,353	498
Securitized reverse residential mortgage loan	0	89	0	174
FVO consolidated securitization entities - changes in estimated fair value included in net investment gains (losses):
Commercial mortgage loans	34	44	71	89
Securities	2	1	2	3
Subtotal	350	(383)	1,426	764
Net investment income	5,282	4,719	11,359	10,919
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	(24)	(5)	(14)	24
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	$ 123	$ (378)	$ 1,078	$ 499

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

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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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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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Securitized reverse residential mortgage loan.

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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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Aggregate amount of net income allocated to limited partners.

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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.

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The amount of investment earnings, excluding realized and unrealized gain (loss), recognized in the period on investments that the entity intends to hold for at least a year which are not otherwise specified in the disclosed schedule of investments, net of related investment expenses.

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