Condensed Consolidated Statements of Equity - USD ($) $ in Millions	Total	Total AIG Shareholders' Equity	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income	Non redeemable Non-controlling Interests
Balance at Dec. 31, 2016	$ 76,858	$ 76,300	$ 4,766	$ (41,471)	$ 81,064	$ 28,711	$ 3,230	$ 558
Increase (Decrease) in Stockholders' Equity
Common stock issued under stock plans	(164)	(164)	0	140	(304)	0	0	0
Purchase of common stock	(6,275)	(6,275)	0	(6,275)	0	0	0	0
Net income (loss) attributable to AIG or noncontrolling interests	616	576	0	0	0	576	0	40
Dividends	(884)	(884)	0	0	0	(884)	0	0
Other comprehensive income (loss)	2,709	2,709	0	0	0	0	2,709	0
Current and deferred income taxes	(4)	(4)	0	0	(4)	0	0	0
Net increase due to acquisitions and consolidations	78	0	0	0	0	0	0	78
Contributions from noncontrolling interests	13	0	0	0	0	0	0	13
Distributions to noncontrolling interests	(131)	0	0	0	0	0	0	(131)
Other	196	210	0	4	220	(14)	0	(14)
Balance at Sep. 30, 2017	73,012	72,468	4,766	(47,602)	80,976	28,389	5,939	544
Increase (Decrease) in Stockholders' Equity
Cumulative effect of change in accounting principle, net of tax	0	0	0	0	0	0	0	0
Balance at Jun. 30, 2017	74,324	73,732	4,766	(47,329)	80,913	30,420	4,962	592
Increase (Decrease) in Stockholders' Equity
Common stock issued under stock plans	0	0	0	0	0	0	0	0
Purchase of common stock	(275)	(275)	0	(275)	0	0	0	0
Net income (loss) attributable to AIG or noncontrolling interests	(1,713)	(1,739)	0	0	0	(1,739)	0	26
Dividends	(287)	(287)	0	0	0	(287)	0	0
Other comprehensive income (loss)	977	977	0	0	0	0	977	0
Current and deferred income taxes	0	0	0	0	0	0	0	0
Net increase due to acquisitions and consolidations	32	0	0	0	0	0	0	32
Contributions from noncontrolling interests	(1)	0	0	0	0	0	0	(1)
Distributions to noncontrolling interests	(49)	0	0	0	0	0	0	(49)
Other	4	60	0	2	63	(5)	0	(56)
Balance at Sep. 30, 2017	73,012	72,468	4,766	(47,602)	80,976	28,389	5,939	544
Increase (Decrease) in Stockholders' Equity
Cumulative effect of change in accounting principle, net of tax	(8)	(8)	0	0	0	568	(576)	0
Balance at Dec. 31, 2017	65,708	65,171	4,766	(47,595)	81,078	21,457	5,465	537
Increase (Decrease) in Stockholders' Equity
Common stock issued under stock plans	(150)	(150)	0	187	(337)	0	0	0
Purchase of common stock	(994)	(994)	0	(994)	0	0	0	0
Net income (loss) attributable to AIG or noncontrolling interests	621	616	0	0	0	616	0	5
Dividends	858	(858)	0	0	0	(858)	0	0
Other comprehensive income (loss)	(5,425)	(5,425)	0	0	0	0	(5,425)	0
Current and deferred income taxes	0	0	0	0	0	0	0	0
Net increase due to acquisitions and consolidations	99	0	0	0	0	0	0	99
Contributions from noncontrolling interests	21	0	0	0	0	0	0	21
Distributions to noncontrolling interests	(65)	0	0	0	0	0	0	(65)
Other	228	234	0	1	267	(34)	0	(6)
Balance at Sep. 30, 2018	59,177	58,586	4,766	(48,401)	81,008	21,749	(536)	591
Increase (Decrease) in Stockholders' Equity
Cumulative effect of change in accounting principle, net of tax			0	0	0		0
Balance at Jun. 30, 2018	61,797	61,186	4,766	(48,052)	80,924	23,318	230	611
Increase (Decrease) in Stockholders' Equity
Common stock issued under stock plans	0	0	0	0	0	0	0	0
Purchase of common stock	(348)	(348)	0	(348)	0	0	0	0
Net income (loss) attributable to AIG or noncontrolling interests	(1,259)	(1,259)	0	0	0	(1,259)	0	0
Dividends	(283)	(283)	0	0	0	(283)	0	0
Other comprehensive income (loss)	(766)	(766)	0	0	0	0	(766)	0
Current and deferred income taxes	0	0	0	0	0	0	0	0
Net increase due to acquisitions and consolidations	1	0	0	0	0	0	0	1
Contributions from noncontrolling interests	18	0	0	0	0	0	0	18
Distributions to noncontrolling interests	(38)	0	0	0	0	0	0	(38)
Other	55	56	0	(1)	84	(27)	0	(1)
Balance at Sep. 30, 2018	$ 59,177	$ 58,586	$ 4,766	$ (48,401)	$ 81,008	$ 21,749	$ (536)	$ 591