Fair Value Measurements (Details 6) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2011 Private equity funds	Dec. 31, 2010 Private equity funds
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	$ 7,302	$ 7,920
Unfunded Commitments	1,288	1,496
Investments of entities classified as held for sale	3	415
Private equity funds:
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	4,299	4,265
Unfunded Commitments	1,276	1,474
Expected remaining lives that funds in some cases extend beyond (in years)	10
Investment redemption notice period (in days/years)	1 years
Private equity funds: \| Expected remaining lives of less than 3 years
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
First threshold level of remaining lives (in years)	3
Percentage of hedge fund investments that cannot be redeemed, either in whole or in part (as a percent)	36.00%
Private equity funds: \| Expected remaining lives of less than 3 to 7 years
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Second threshold level of remaining lives (in years)	7
Percentage of hedge fund investments that cannot be redeemed, either in whole or in part (as a percent)	53.00%
Private equity funds: \| Expected remaining lives of less than 7 to 10 years
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Third threshold level of remaining lives (in years)	10
Percentage of hedge fund investments that cannot be redeemed, either in whole or in part (as a percent)	11.00%
Leveraged buyout
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	3,241	3,137
Unfunded Commitments	996	1,151
Non-U.S.
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	199	172
Unfunded Commitments	64	67
Venture capital
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	337	325
Unfunded Commitments	46	42
Distressed
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	222	258
Unfunded Commitments	62	67
Other.
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	300	373
Unfunded Commitments	108	147
Hedge funds:
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	3,003	3,655
Unfunded Commitments	12	22
Hedge fund investments redeemable monthly (as a percent)	12.00%
Hedge fund investments redeemable quarterly (as a percent)	52.00%
Hedge fund investments redeemable semi-annually (as a percent)	8.00%
Hedge fund investments redeemable annually (as a percent)	28.00%
Hedge fund investments redemption notices of less than 90 days (as a percent)	82.00%
Percentage of hedge fund investments that cannot be redeemed, either in whole or in part (as a percent)	54.00%
Investment redemption notice period (in days/years)	1 day to 180 days
Event-driven
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	922	1,310
Unfunded Commitments	2	2
Long-short
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	1,004	1,038
Relative value
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	87	230
Distressed.
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	323	369
Unfunded Commitments	10	20
Other hedge funds
Investments in Certain Entities Carried at Fair Value Using Net Asset Value per Share
Fair Value Using Net Asset Value	$ 667	$ 708

The number of years representing the first threshold of the expected remaining lives of less than three years of investments.

Name:	aig_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLiquidatingInvestmentRemainingPeriodThresholdLevelOne
Namespace Prefix:	aig
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of years representing the third threshold of the expected remaining lives between seven and ten years of investments.

+ Details

Name:	aig_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLiquidatingInvestmentRemainingPeriodThresholdLevelThree
Namespace Prefix:	aig
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of years representing the second threshold of the expected remaining lives between three and seven years of investments.

+ Details

Name:	aig_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLiquidatingInvestmentRemainingPeriodThresholdLevelTwo
Namespace Prefix:	aig
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The total fair value for all available for sale investments of held for sale entities for which net asset value per share is calculated.

+ Details

Name:	aig_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerSharePlannedSaleInvestmentsIdentifiedValue
Namespace Prefix:	aig
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the percentage of investment subject to annual redemption.

+ Details

Name:	aig_PercentageOfAnnualRedemption
Namespace Prefix:	aig
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the percentage of investment subject to monthly redemption.

+ Details

Name:	aig_PercentageOfMonthlyRedemption
Namespace Prefix:	aig
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the percentage of investment subject to quarterly redemption.

+ Details

Name:	aig_PercentageOfQuarterlyRedemption
Namespace Prefix:	aig
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the percentage of investment funds that are subject to a redemption period of less than 90 days.

+ Details

Name:	aig_PercentageOfRedemptionInvestmentFunds
Namespace Prefix:	aig
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the percentage of investment subject to semi-annual redemption.

+ Details

Name:	aig_PercentageOfSemiAnnualRedemption
Namespace Prefix:	aig
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the total fair market value of investments in certain entities that calculate net asset value per share (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments). This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements, but may also be used in both the balance sheet and disclosure in the same submission. This item represents alternative investments as of the balance sheet date which may include investments in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds, and any other investment in which investee management calculates net asset value per share as the primary metric for investment value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph a
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph a
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19296-110258

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Subparagraph (a)
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=6925170&loc=SL6742756-110258

+ Details

Name:	us-gaap_AlternativeInvestmentsFairValueDisclosure
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

States the notice requirement (for example, 30 to 60 days) the entity is required to deliver before it can redeem its investment, or portion thereof, for each of those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments), by major category.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=SL6742756-110258

+ Details

Name:	us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareInvestmentRedemptionNoticePeriod
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

Name:	us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the remaining period (for example, years, months, days) for those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments) that the entity can never redeem, but from which the entity receives distributions through the liquidation of the underlying assets by the investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=SL6742756-110258

+ Details

Name:	us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLiquidatingInvestmentRemainingPeriod
Namespace Prefix:	us-gaap
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of the total value of investments that cannot be redeemed because of a redemption restriction as of the statement of financial position date.

+ Details

Name:	us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareRedemptionRestrictionPercentage
Namespace Prefix:	us-gaap
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=SL6742756-110258

+ Details

Name:	us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant