Equity - Schedule of Effect of the Reclassification of Significant Items out of Accumulated Other Comprehensive Income on the Respective Line Items in the Consolidated Statements of Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized losses	$ (424)	$ (1,909)
Net income (loss) attributable to AIG	1,216	30
Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Net income (loss) attributable to AIG	(450)	(461)
Unrealized appreciation (depreciation) of fixed maturity securities on which allowance for credit losses was taken | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized losses	(6)	(16)
Unrealized appreciation (depreciation) of all other investments | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized losses	(437)	(436)
Change in retirement plan liabilities adjustment | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized losses	(7)	(9)
Prior-service credit | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized losses	0	(1)
Actuarial losses | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized losses	$ (7)	$ (8)