Condensed Consolidated Statements of Equity - USD ($) $ in Millions	Total	Cumulative effect of change in accounting principle	Total AIG Shareholders' Equity	Total AIG Shareholders' Equity Cumulative effect of change in accounting principle	Preferred Stock and Additional Paid-In Capital	Preferred Stock and Additional Paid-In Capital Cumulative effect of change in accounting principle	Common Stock	Common Stock Cumulative effect of change in accounting principle	Treasury Stock	Treasury Stock Cumulative effect of change in accounting principle	Additional Paid-in Capital	Additional Paid-in Capital Cumulative effect of change in accounting principle	Retained Earnings	Retained Earnings Cumulative effect of change in accounting principle	Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income Cumulative effect of change in accounting principle	Non-redeemable Non-controlling Interests	Non-redeemable Non-controlling Interests Cumulative effect of change in accounting principle
Balance at Dec. 31, 2019	$ 67,427	$ (487)	$ 65,675	$ (487)	$ 485	$ 0	$ 4,766	$ 0	$ (48,987)	$ 0	$ 81,345	$ 0	$ 23,084	$ (487)	$ 4,982	$ 0	$ 1,752	$ 0
Common stock issued under stock plans	(98)		(98)		0		0		167		(265)		0		0		0
Purchase of common stock	(500)		(500)		0		0		(500)		0		0		0		0
Net income (loss) attributable to AIG or noncontrolling interests	(5,813)		(5,891)		0		0		0		0		(5,891)		0		78
Dividends on preferred stock	(22)		(22)		0		0		0		0		(22)		0		0
Dividends on common stock	(827)		(827)		0		0		0		0		(827)		0		0
Other comprehensive income (loss)	5,980		5,996		0		0		0		0		0		5,996		(16)
Net increase due to divestitures and acquisitions	(1,199)		0		0		0		0		0		0		0		(1,199)
Contributions from noncontrolling interests	4		0		0		0		0		0		0		0		4
Distributions to noncontrolling interests	(113)		0		0		0		0		0		0		0		(113)
Other	255		262		0		0		(7)		288		(19)		0		(7)
Balance at Sep. 30, 2020	64,607		64,108		485		4,766		(49,327)		81,368		15,838		10,978		499
Balance at Jun. 30, 2020	62,818		62,234		485		4,766		(49,327)		81,294		15,847		9,169		584
Common stock issued under stock plans	(1)		(1)		0		0		0		(1)		0		0		0
Purchase of common stock	0		0		0		0		0		0		0		0		0
Net income (loss) attributable to AIG or noncontrolling interests	299		288		0		0		0		0		288		0		11
Dividends on preferred stock	(7)		(7)		0		0		0		0		(7)		0		0
Dividends on common stock	(276)		(276)		0		0		0		0		(276)		0		0
Other comprehensive income (loss)	1,816		1,809		0		0		0		0		0		1,809		7
Net increase due to divestitures and acquisitions	(28)		0		0		0		0		0		0		0		(28)
Contributions from noncontrolling interests	0		0		0		0		0		0		0		0		0
Distributions to noncontrolling interests	(71)		0		0		0		0		0		0		0		(71)
Other	57		61		0		0		0		75		(14)		0		(4)
Balance at Sep. 30, 2020	64,607		64,108		485		4,766		(49,327)		81,368		15,838		10,978		499
Balance at Dec. 31, 2020	67,199		66,362		485		4,766		(49,322)		81,418		15,504		13,511		837
Common stock issued under stock plans	(77)		(77)		0		0		202		(279)		0		0		0
Purchase of common stock	(1,651)		(1,651)		0		0		(1,622)		(29)		0		0		0
Net income (loss) attributable to AIG or noncontrolling interests	5,817		5,642		0		0		0		0		5,642		0		175
Dividends on preferred stock	(22)		(22)		0		0		0		0		(22)		0		0
Dividends on common stock	(819)		(819)		0		0		0		0		(819)		0		0
Other comprehensive income (loss)	(4,905)		(4,905)		0		0		0		0		0		(4,905)		0
Net increase due to divestitures and acquisitions	50		0		0		0		0		0		0		0		50
Contributions from noncontrolling interests	8		0		0		0		0		0		0		0		8
Distributions to noncontrolling interests	(279)		0		0		0		0		0		0		0		(279)
Other	338		333		0		0		101		217		15		0		5
Balance at Sep. 30, 2021	65,659		64,863		485		4,766		(50,641)		81,327		20,320		8,606		796
Balance at Jun. 30, 2021	66,908		66,083		485		4,766		(49,634)		81,322		18,935		10,209		825
Common stock issued under stock plans	5		5		0		0		24		(19)		0		0		0
Purchase of common stock	(1,059)		(1,059)		0		0		(1,030)		(29)		0		0		0
Net income (loss) attributable to AIG or noncontrolling interests	1,737		1,667		0		0		0		0		1,667		0		70
Dividends on preferred stock	(7)		(7)		0		0		0		0		(7)		0		0
Dividends on common stock	(269)		(269)		0		0		0		0		(269)		0		0
Other comprehensive income (loss)	(1,602)		(1,603)		0		0		0		0		0		(1,603)		1
Net increase due to divestitures and acquisitions	(8)		0		0		0		0		0		0		0		(8)
Contributions from noncontrolling interests	1		0		0		0		0		0		0		0		1
Distributions to noncontrolling interests	(98)		0		0		0		0		0		0		0		(98)
Other	51		46		0		0		(1)		53		(6)		0		5
Balance at Sep. 30, 2021	$ 65,659		$ 64,863		$ 485		$ 4,766		$ (50,641)		$ 81,327		$ 20,320		$ 8,606		$ 796