Insurance Liabilities - Net loss reserve discount benefit (charge) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net Loss Reserve Discount Benefit (Charge) [Line Items]
Current accident year	$ 98	$ 62	$ 71
Accretion and other adjustments to prior year discount	(239)	(88)	(180)
Net reserve discount benefit (charge)	703	193	(516)
Change in discount on loss reserves ceded under retroactive reinsurance	(301)	(42)	340
Net change in total reserve discount	402	151	(176)
North America Commercial Insurance
Net Loss Reserve Discount Benefit (Charge) [Line Items]
Effect of interest rate changes	844	219	(407)
United Kingdom
Net Loss Reserve Discount Benefit (Charge) [Line Items]
Net change in total reserve discount	$ 19	$ (35)	$ (20)

Represents the increase (decrease) in discount of loss reserves.

No definition available.

Name:	aig_IncreaseDecreaseInLossReserveDiscount
Namespace Prefix:	aig_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the increase (decrease) in discount of loss reserves attributable to current accident year loss reserve activities.

No definition available.

Name:	aig_IncreaseDecreaseInLossReserveDiscountCurrentYear
Namespace Prefix:	aig_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Increase (Decrease) In Loss Reserve Discount, Effect Of Interest Rate Changes

No definition available.

Name:	aig_IncreaseDecreaseInLossReserveDiscountEffectOfInterestRateChanges
Namespace Prefix:	aig_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the net change in discount of loss reserves.

No definition available.

Name:	aig_IncreaseDecreaseInLossReserveDiscountIncludingReinsurance
Namespace Prefix:	aig_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the increase (decrease) in discount of loss reserves attributable to prior year year loss reserve development and payout pattern

No definition available.

Name:	aig_IncreaseDecreaseInLossReserveDiscountPriorYear
Namespace Prefix:	aig_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the increase (decrease) in discount of loss reserves due to reinsurance transaction.

No definition available.

Name:	aig_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseRetroactiveReinsuranceDiscount
Namespace Prefix:	aig_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Net loss reserve discount benefit (charge) [Line Items]

No definition available.

Name:	aig_NetLossReserveDiscountBenefitChargeLineItems
Namespace Prefix:	aig_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Name:	srt_ProductOrServiceAxis=aig_NorthAmericanCommercialInsuranceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_StatementGeographicalAxis=country_GB
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: