Fair Value Measurements (Details 3) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Assets
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	$ 35,281	$ 34,819	$ 34,656	$ 37,145
Net Realized and Unrealized Gains (Losses) Included in Income	(782)	466	263	1,035
Accumulated Other Comprehensive Loss	(29)	1,106	1,763	2,817
Purchases, Sales, Issuances and Settlements-Net	3,683	(562)	2,996	(2,149)
Gross Transfers in, assets	866		1,305
Gross Transfers out, assets	(191)		(2,155)
Net Transfers		(209)		(43)
Activity of Discontinued Operations		953		(2,232)
Balance End of Period	38,828	36,573	38,828	36,573
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, assets	(535)	610	341	1,981
Obligations of states, municipalities and Political subdivisions | Bonds available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	702	948	609	613
Net Realized and Unrealized Gains (Losses) Included in Income	(1)	(7)	(1)	(21)
Accumulated Other Comprehensive Loss	23	(6)	27	(13)
Purchases, Sales, Issuances and Settlements-Net	62	49	174	158
Gross Transfers in, assets	17		17
Gross Transfers out, assets	(3)		(26)
Net Transfers		101		349
Activity of Discontinued Operations		1
Balance End of Period	800	1,086	800	1,086
Non-U.S. government | Bonds available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	5	5	5	753
Purchases, Sales, Issuances and Settlements-Net	0	24	0	24
Net Transfers	0	5	0	5
Activity of Discontinued Operations	0	8	0	(740)
Balance End of Period	5	42	5	42
Corporate debt | Bonds available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	1,235	3,917	2,262	4,791
Net Realized and Unrealized Gains (Losses) Included in Income		9	(3)	(10)
Accumulated Other Comprehensive Loss	15	16	22	102
Purchases, Sales, Issuances and Settlements-Net	305	(126)	272	(235)
Gross Transfers in, assets	307		533
Gross Transfers out, assets	(18)		(1,242)
Net Transfers		(853)		(1,388)
Activity of Discontinued Operations		204		(93)
Balance End of Period	1,844	3,167	1,844	3,167
Prime residential mortgages | Bonds available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	6,868	6,832	6,367	6,654
Net Realized and Unrealized Gains (Losses) Included in Income	79	(122)	(2)	(241)
Accumulated Other Comprehensive Loss	(165)	550	368	992
Purchases, Sales, Issuances and Settlements-Net	3,905	(164)	3,943	(306)
Gross Transfers in, assets	11		22
Gross Transfers out, assets	(6)		(6)
Net Transfers		19		50
Activity of Discontinued Operations		(1)		(35)
Balance End of Period	10,692	7,114	10,692	7,114
Commercial mortgage-backed securities (CMBS) | Bonds available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	4,316	4,396	3,604	4,939
Net Realized and Unrealized Gains (Losses) Included in Income	(7)	(264)	(34)	(582)
Accumulated Other Comprehensive Loss	(109)	437	555	1,075
Purchases, Sales, Issuances and Settlements-Net		(63)	72	(154)
Gross Transfers in, assets	28		53
Gross Transfers out, assets			(22)
Net Transfers		(5)		447
Activity of Discontinued Operations		75		(1,149)
Balance End of Period	4,228	4,576	4,228	4,576
Multi-sector CDOs | Bonds available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	3,857	4,576	4,241	4,724
Net Realized and Unrealized Gains (Losses) Included in Income	12	53	32	74
Accumulated Other Comprehensive Loss	74	19	312	275
Purchases, Sales, Issuances and Settlements-Net	(382)	(148)	(837)	(160)
Gross Transfers in, assets	374		446
Gross Transfers out, assets	(10)		(269)
Net Transfers		75		106
Activity of Discontinued Operations		262		(182)
Balance End of Period	3,925	4,837	3,925	4,837
Bonds available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	16,983	20,674	17,088	22,474
Net Realized and Unrealized Gains (Losses) Included in Income	83	(331)	(8)	(780)
Accumulated Other Comprehensive Loss	(162)	1,016	1,284	2,431
Purchases, Sales, Issuances and Settlements-Net	3,890	(428)	3,624	(673)
Gross Transfers in, assets	737		1,071
Gross Transfers out, assets	(37)		(1,565)
Net Transfers		(658)		(431)
Activity of Discontinued Operations		549		(2,199)
Balance End of Period	21,494	20,822	21,494	20,822
U.S. government and government sponsored entities | Bond trading securities
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period				16
Activity of Discontinued Operations				(16)
Non-U.S. government | Bond trading securities
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period		2		56
Purchases, Sales, Issuances and Settlements-Net		(1)		(51)
Net Transfers		6		8
Activity of Discontinued Operations				(6)
Balance End of Period		7		7
Corporate debt | Bond trading securities
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	18	7		121
Net Realized and Unrealized Gains (Losses) Included in Income		(11)		(16)
Accumulated Other Comprehensive Loss		(2)
Purchases, Sales, Issuances and Settlements-Net	(9)	(2)	(9)	(2)
Gross Transfers in, assets			18
Activity of Discontinued Operations		109		(2)
Balance End of Period	9	101	9	101
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, assets		(5)		(10)
Prime residential mortgages | Bond trading securities
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	99	5	91	4
Net Realized and Unrealized Gains (Losses) Included in Income	(2)	1		2
Accumulated Other Comprehensive Loss	(7)	2	(7)	2
Purchases, Sales, Issuances and Settlements-Net	80		86
Balance End of Period	170	8	170	8
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, assets	(5)	1	(3)	2
Commercial mortgage-backed securities (CMBS) | Bond trading securities
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	523	294	506	325
Net Realized and Unrealized Gains (Losses) Included in Income	28	20	66	60
Accumulated Other Comprehensive Loss	3		3
Purchases, Sales, Issuances and Settlements-Net	(18)	(88)	(76)	(95)
Gross Transfers in, assets	80		161
Gross Transfers out, assets	(133)		(177)
Net Transfers				34
Activity of Discontinued Operations				(98)
Balance End of Period	483	226	483	226
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, assets	29	29	68	130
Multi-sector CDOs | Bond trading securities
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	10,461	7,895	9,431	6,865
Net Realized and Unrealized Gains (Losses) Included in Income	(877)	673	153	1,790
Accumulated Other Comprehensive Loss	4		9
Purchases, Sales, Issuances and Settlements-Net	(85)	(49)	(90)	(136)
Net Transfers		3		3
Balance End of Period	9,503	8,522	9,503	8,522
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, assets	(881)	708	146	2,008
Bond trading securities
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	11,101	8,203	10,028	7,387
Net Realized and Unrealized Gains (Losses) Included in Income	(851)	683	219	1,836
Accumulated Other Comprehensive Loss			5	2
Purchases, Sales, Issuances and Settlements-Net	(32)	(140)	(89)	(284)
Gross Transfers in, assets	80		179
Gross Transfers out, assets	(133)		(177)
Net Transfers		9		45
Activity of Discontinued Operations		109		(122)
Balance End of Period	10,165	8,864	10,165	8,864
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, assets	(857)	733	211	2,130
Common Stock | Equity securities available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	63	36	61	35
Net Realized and Unrealized Gains (Losses) Included in Income	3	2	18
Accumulated Other Comprehensive Loss	6	(4)	4	1
Purchases, Sales, Issuances and Settlements-Net	(12)	(6)	(27)	(5)
Gross Transfers in, assets	2		8
Gross Transfers out, assets	(3)		(5)
Net Transfers		3		3
Activity of Discontinued Operations		2		(1)
Balance End of Period	59	33	59	33
Preferred Stock. | Equity securities available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	63	52	64	54
Net Realized and Unrealized Gains (Losses) Included in Income	(1)	4	(3)	(1)
Accumulated Other Comprehensive Loss	1	2	1	4
Purchases, Sales, Issuances and Settlements-Net	(1)	(1)		(1)
Gross Transfers in, assets	2		2
Net Transfers				1
Balance End of Period	64	57	64	57
Mutual Funds | Equity securities available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period				6
Net Realized and Unrealized Gains (Losses) Included in Income		(5)		(5)
Accumulated Other Comprehensive Loss		(1)		(1)
Purchases, Sales, Issuances and Settlements-Net		8		8
Net Transfers		7		7
Activity of Discontinued Operations		6
Balance End of Period		15		15
Equity securities available for sale
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	126	88	125	95
Net Realized and Unrealized Gains (Losses) Included in Income	2	1	15	(6)
Accumulated Other Comprehensive Loss	7	(3)	5	4
Purchases, Sales, Issuances and Settlements-Net	(13)	1	(27)	2
Gross Transfers in, assets	4		10
Gross Transfers out, assets	(3)		(5)
Net Transfers		10		11
Activity of Discontinued Operations		8		(1)
Balance End of Period	123	105	123	105
Equity securities trading
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	1	1	1	8
Net Realized and Unrealized Gains (Losses) Included in Income	1		1
Purchases, Sales, Issuances and Settlements-Net	(1)		(1)
Activity of Discontinued Operations		0		(7)
Balance End of Period	1	1	1	1
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, assets	1		1
Other invested assets
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period	7,070	5,853	7,414	6,910
Net Realized and Unrealized Gains (Losses) Included in Income	(17)	113	36	(15)
Accumulated Other Comprehensive Loss	126	93	469	380
Purchases, Sales, Issuances and Settlements-Net	(161)	5	(511)	(924)
Gross Transfers in, assets	45		45
Gross Transfers out, assets	(18)		(408)
Net Transfers		429		331
Activity of Discontinued Operations		287		98
Balance End of Period	7,045	6,780	7,045	6,780
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, assets	321	(123)	129	(149)
Other assets.
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period				270
Purchases, Sales, Issuances and Settlements-Net				(270)
Separate account assets
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance Beginning of Period				1
Net Transfers		1		1
Activity of Discontinued Operations				(1)
Balance End of Period		1		1
Liabilities
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance at the Beginning of the Period	(4,107)	(7,986)	(4,544)	(12,160)
Net Realized and Unrealized Gains (Losses) Included in Income	2	(212)	293	139
Accumulated Other Comprehensive Loss	(51)	(1)	(26)	(2)
Purchases, Sales, Issuances and Settlements-Net	163	185	297	165
Gross Transfers in, liabilities	25		4
Gross Transfers out, liabilities			8
Net Transfers		976		294
Activity of Discontinued Operations		(2,924)		1,602
Balance at the End of the Period	(3,968)	(9,962)	(3,968)	(9,962)
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, liabilities	(60)	290	86	231
Policyholder contract deposits
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance at the Beginning of the Period	(369)	(641)	(445)	(5,214)
Net Realized and Unrealized Gains (Losses) Included in Income	(33)	(820)	46	(624)
Purchases, Sales, Issuances and Settlements-Net	(4)	(129)	(7)	(268)
Activity of Discontinued Operations		(2,920)		1,596
Balance at the End of the Period	(406)	(4,510)	(406)	(4,510)
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, liabilities	30	869	(63)	684
Derivative liabilities, net
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance at the Beginning of the Period	(2,742)	(6,222)	(3,117)	(6,065)
Net Realized and Unrealized Gains (Losses) Included in Income	192	535	458	825
Accumulated Other Comprehensive Loss	(51)	(1)	(26)	(2)
Purchases, Sales, Issuances and Settlements-Net	(28)	247	48	(189)
Gross Transfers in, liabilities	25		25
Gross Transfers out, liabilities			8
Net Transfers		947		927
Activity of Discontinued Operations		(4)		6
Balance at the End of the Period	(2,604)	(4,498)	(2,604)	(4,498)
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, liabilities	66	(505)	347	(515)
Interest rate contracts
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance at the Beginning of the Period	619	(1,286)	732	(1,469)
Net Realized and Unrealized Gains (Losses) Included in Income	138	435	22	533
Accumulated Other Comprehensive Loss		(1)		(1)
Purchases, Sales, Issuances and Settlements-Net	(3)	99		195
Net Transfers		904		893
Balance at the End of the Period	754	151	754	151
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, liabilities	(29)	173	(54)	6
Foreign exchange contracts
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance at the Beginning of the Period	16	29	16	29
Net Realized and Unrealized Gains (Losses) Included in Income	(12)	1	(12)
Accumulated Other Comprehensive Loss				(1)
Purchases, Sales, Issuances and Settlements-Net		(3)		(3)
Activity of Discontinued Operations		(3)		(1)
Balance at the End of the Period	4	24	4	24
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, liabilities	1	(13)	1	(10)
Equity contracts
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance at the Beginning of the Period	34	55	22	74
Net Realized and Unrealized Gains (Losses) Included in Income		(53)	(7)	(63)
Purchases, Sales, Issuances and Settlements-Net		(31)	38	(31)
Gross Transfers in, liabilities	(7)		(7)
Gross Transfers out, liabilities	7		(12)
Net Transfers		29		20
Balance at the End of the Period	34		34
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, liabilities		5	(7)	(1)
Commodity contracts
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance at the Beginning of the Period	15	20	23	22
Net Realized and Unrealized Gains (Losses) Included in Income	(1)	(3)	2	(5)
Purchases, Sales, Issuances and Settlements-Net	(9)		(20)
Balance at the End of the Period	5	17	5	17
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, liabilities	(2)	6		4
Credit contracts
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance at the Beginning of the Period	(3,420)	(4,910)	(3,798)	(4,545)
Net Realized and Unrealized Gains (Losses) Included in Income	94	162	476	326
Purchases, Sales, Issuances and Settlements-Net	(6)	166	(10)	(363)
Net Transfers		(1)		(1)
Balance at the End of the Period	(3,332)	(4,583)	(3,332)	(4,583)
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, liabilities	92	(650)	473	(485)
Other contracts
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance at the Beginning of the Period	(6)	(130)	(112)	(176)
Net Realized and Unrealized Gains (Losses) Included in Income	(27)	(7)	(23)	34
Accumulated Other Comprehensive Loss	(51)		(26)
Purchases, Sales, Issuances and Settlements-Net	(10)	16	40	13
Gross Transfers in, liabilities	32		32
Gross Transfers out, liabilities	(7)		20
Net Transfers		15		15
Activity of Discontinued Operations		(1)		7
Balance at the End of the Period	(69)	(107)	(69)	(107)
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, liabilities	4	(26)	(66)	(29)
Other long-term debt
Fair value assets and liabilities measured on recurring basis, unobservable input reconciliation calculation
Balance at the Beginning of the Period	(996)	(1,123)	(982)	(881)
Net Realized and Unrealized Gains (Losses) Included in Income	(157)	73	(211)	(62)
Purchases, Sales, Issuances and Settlements-Net	195	67	256	622
Gross Transfers in, liabilities			(21)
Net Transfers		29		(633)
Balance at the End of the Period	(958)	(954)	(958)	(954)
Changes in Unrealized Gains (Losses) on Instruments Held at End of Period, liabilities	$ (156)	$ (74)	$ (198)	$ 62