Employee Benefits - Schedule of assumed health care cost trend rates (Details) - U.S. Plans - Pension	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Ultimate rate to which cost increase is assumed to decline	4.00%	4.00%
Before age 65
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Following year	5.78%	6.01%
Year in which the ultimate trend rate is reached	2046	2046
Age 65 And Older
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Following year	4.93%	4.95%
Year in which the ultimate trend rate is reached	2046	2046

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

+ Details

Name:	us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Year ultimate health care cost trend rate is expected to be reached, in YYYY format.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:gYearListItemType
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.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RetirementPlanSponsorLocationAxis=country_US
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	aig_AgeCriteriaForMedicalBenefitsAxis=aig_BeforeAge65Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	aig_AgeCriteriaForMedicalBenefitsAxis=aig_Age65AndOlderMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: