Investments (Details 2) (USD $) In Millions, unless otherwise specified	Jun. 30, 2011	Dec. 31, 2010
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	$ 38,541	$ 37,686
Gross Unrealized Losses, 12 Months or Less	1,326	1,209
Fair Value, More than 12 Months	14,768	20,119
Gross Unrealized Losses, More than 12 Months	2,293	3,930
Fair Value, total	53,309	57,805
Gross Unrealized Losses, total	3,619	5,139
Number of individual securities in continuous unrealized loss position for longer than twelve months (in securities)	2,075
Fixed maturity securities
Fair value and gross unrealized losses on AIG's available for sale securities
Number of individual fixed maturity securities (in securities)	6,330
U.S. government and government sponsored entities \| Bonds available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	2,266	2,142
Gross Unrealized Losses, 12 Months or Less	28	73
Fair Value, total	2,266	2,142
Gross Unrealized Losses, total	28	73
Obligations of states, municipalities and Political subdivisions \| Bonds available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	3,890	9,300
Gross Unrealized Losses, 12 Months or Less	86	296
Fair Value, More than 12 Months	640	646
Gross Unrealized Losses, More than 12 Months	89	106
Fair Value, total	4,530	9,946
Gross Unrealized Losses, total	175	402
Non-U.S. government \| Bonds available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	2,777	1,427
Gross Unrealized Losses, 12 Months or Less	89	34
Fair Value, More than 12 Months	135	335
Gross Unrealized Losses, More than 12 Months	9	41
Fair Value, total	2,912	1,762
Gross Unrealized Losses, total	98	75
Corporate debt \| Bonds available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	18,982	18,246
Gross Unrealized Losses, 12 Months or Less	505	579
Fair Value, More than 12 Months	5,500	7,343
Gross Unrealized Losses, More than 12 Months	441	619
Fair Value, total	24,482	25,589
Gross Unrealized Losses, total	946	1,198
Prime residential mortgages \| Bonds available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	7,729	4,461
Gross Unrealized Losses, 12 Months or Less	414	105
Fair Value, More than 12 Months	4,651	6,178
Gross Unrealized Losses, More than 12 Months	844	1,448
Fair Value, total	12,380	10,639
Gross Unrealized Losses, total	1,258	1,553
Commercial mortgage-backed securities (CMBS) \| Bonds available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	1,717	462
Gross Unrealized Losses, 12 Months or Less	141	19
Fair Value, More than 12 Months	1,866	3,014
Gross Unrealized Losses, More than 12 Months	552	1,130
Fair Value, total	3,583	3,476
Gross Unrealized Losses, total	693	1,149
Multi-sector CDOs \| Bonds available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	775	996
Gross Unrealized Losses, 12 Months or Less	24	48
Fair Value, More than 12 Months	1,976	2,603
Gross Unrealized Losses, More than 12 Months	358	586
Fair Value, total	2,751	3,599
Gross Unrealized Losses, total	382	634
Bonds available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	38,136	37,034
Gross Unrealized Losses, 12 Months or Less	1,287	1,154
Fair Value, More than 12 Months	14,768	20,119
Gross Unrealized Losses, More than 12 Months	2,293	3,930
Fair Value, total	52,904	57,153
Gross Unrealized Losses, total	3,580	5,084
Equity securities
Fair value and gross unrealized losses on AIG's available for sale securities
Number of equity securities in an unrealized loss position (in securities)	145
Common Stock \| Equity securities available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	390	576
Gross Unrealized Losses, 12 Months or Less	38	52
Fair Value, total	390	576
Gross Unrealized Losses, total	38	52
Preferred Stock. \| Equity securities available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	11	11
Gross Unrealized Losses, 12 Months or Less		1
Fair Value, total	11	11
Gross Unrealized Losses, total		1
Mutual Funds \| Equity securities available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	4	65
Gross Unrealized Losses, 12 Months or Less	1	2
Fair Value, total	4	65
Gross Unrealized Losses, total	1	2
Equity securities available for sale
Fair value and gross unrealized losses on AIG's available for sale securities
Fair Value, 12 Months or Less	405	652
Gross Unrealized Losses, 12 Months or Less	39	55
Fair Value, total	405	652
Gross Unrealized Losses, total	$ 39	$ 55

The number of securities that have been in a continuous unrealized loss position for longer than twelve months.

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