Segment Information - Schedule of Continuing Operations by Operating Segment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting Information [Line Items]
Net Premiums Earned	$ 23,751	$ 23,537	$ 25,564
Loss and Loss Adjustment Expenses Incurred	14,162	14,567	15,393
Amortization of DAC	3,371	3,425	3,771
General Operating Expense	5,053	5,529	5,399
Net Investment Income	4,215	4,255	3,446
Income from continuing operations before income tax expense	3,879	3,870	2,867
Interest expense	396	462	516
Changes in the fair values of equity securities, AIG's investment in Corebridge and gain/loss on sale of shares	255	586	53
Other income (expense) - net	6	16	8
Gain (loss) on extinguishment of debt	5	(14)	37
Total net realized losses	(1,202)	(548)	(1,078)
Net realized gains (losses), net investment income	(4)	8	(12)
Net realized gains (losses), reconciliation to income (loss) from continuing operations before income tax expense	(973)	(428)	(743)
Net gain (loss) on divestitures and other	81	616	(29)
Non-operating litigation reserves and settlements, reconciliation to income (loss) from continuing operations before income tax expense	9		(1)
Unfavorable prior year development and related amortization changes ceded under retroactive reinsurance agreements	(105)	(105)	62
Net loss reserve discount charge	(48)	(226)	(195)
Net results of businesses in run-off, net investment income	31	17	21
Net results of businesses in run-off, net investment income, reconciliation to income (loss) from continuing operations before income tax expense	4	(111)	(31)
Non-operating pension expenses	(15)		(71)
Integration and transaction costs associated with acquiring or divesting businesses	(136)	(39)	(6)
Restructuring and other costs	$ (439)	$ (745)	$ (356)
Restructuring Charges, Statement of Income or Comprehensive Income [Extensible Enumeration]	General Operating Expense	General Operating Expense	General Operating Expense
Non-recurring costs related to regulatory or accounting changes	$ (16)	$ (18)	$ (22)
Net impact from elimination of international reporting lag, net investment income			1
Net impact from elimination of international reporting lag, reconciliation to income (loss) from continuing operations before income tax expense			12
Fortitude Re funds withheld assets
Segment Reporting Information [Line Items]
Net Investment Income	149	144	180
Total net realized losses	(70)	(39)	(71)
Fortitude Re funds withheld embedded derivative
Segment Reporting Information [Line Items]
Total net realized losses	(166)	(75)	(273)
Total
Segment Reporting Information [Line Items]
Net Investment Income	3,778	3,484	3,195
Income from continuing operations before income tax expense	5,344	4,324	4,321
Reportable Segments
Segment Reporting Information [Line Items]
Net Premiums Written	23,675	23,902	26,719
Net Premiums Earned	23,678	23,457	25,091
Loss and Loss Adjustment Expenses Incurred	13,968	14,038	14,775
Amortization of DAC	3,357	3,413	3,623
Other Acquisition Expenses	938	1,137	1,279
General Operating Expense	3,083	2,952	3,065
Underwriting Income (Loss)	2,332	1,917	2,349
Net Investment Income	3,433	3,060	3,022
Income from continuing operations before income tax expense	5,765	4,977	5,371
Interest expense	(392)	(445)	(498)
Other Operations
Segment Reporting Information [Line Items]
Net Premiums Earned	0	0	3
Net Investment Income	346	424	186
Income from continuing operations before income tax expense	(29)	(207)	(535)
Elimination and consolidations
Segment Reporting Information [Line Items]
Net Premiums Earned	(3)	(3)	(5)
Net Investment Income	(1)	0	(13)
Income from continuing operations before income tax expense	0	(1)	(17)
North America Commercial | Reportable Segments
Segment Reporting Information [Line Items]
Net Premiums Written	8,759	8,452	11,432
Net Premiums Earned	8,626	8,172	10,233
Loss and Loss Adjustment Expenses Incurred	5,466	5,713	6,323
Amortization of DAC	862	824	1,371
Other Acquisition Expenses	216	222	231
General Operating Expense	938	865	953
Underwriting Income (Loss)	1,144	548	1,355
International Commercial | Reportable Segments
Segment Reporting Information [Line Items]
Net Premiums Written	8,663	8,364	8,168
Net Premiums Earned	8,580	8,145	7,964
Loss and Loss Adjustment Expenses Incurred	4,781	4,463	4,641
Amortization of DAC	1,088	1,018	943
Other Acquisition Expenses	364	342	350
General Operating Expense	1,229	1,095	1,028
Underwriting Income (Loss)	1,118	1,227	1,002
Global Personal | Reportable Segments
Segment Reporting Information [Line Items]
Net Premiums Written	6,253	7,086	7,119
Net Premiums Earned	6,472	7,140	6,894
Loss and Loss Adjustment Expenses Incurred	3,721	3,862	3,811
Amortization of DAC	1,407	1,571	1,309
Other Acquisition Expenses	358	573	698
General Operating Expense	916	992	1,084
Underwriting Income (Loss)	$ 70	$ 142	$ (8)