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	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized gains (losses)	$ (4,608)	$ 7,064	$ 2,271
Net income attributable to AIG	3,643	10,227	10,367
Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Net income attributable to AIG	(1,091)	(1,212)	882
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 gains (losses)	(26)	7	0
Unrealized appreciation (depreciation) of all other investments | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized gains (losses)	(1,036)	(1,189)	928
Change in retirement plan liabilities adjustment | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized gains (losses)	(29)	(30)	(46)
Prior-service credit | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized gains (losses)	(2)	(2)	(3)
Actuarial losses | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized gains (losses)	$ (27)	$ (28)	$ (43)