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, 2023	Mar. 31, 2022
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized gains (losses)	$ (1,909)	$ 3,579
Net income (loss) attributable to AIG	30	4,173
Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Net income (loss) attributable to AIG	(461)	(147)
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)	(16)	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)	(436)	(139)
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)	(9)	(8)
Prior-service credit | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized gains (losses)	(1)	(1)
Actuarial losses | Amount Reclassified from AOCI
Reclassification of significant items out of Accumulated Other Comprehensive Income
Total net realized gains (losses)	$ (8)	$ (7)