EARNINGS PER SHARE (EPS) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Numerator for EPS:
Income (Loss) from Continuing Operations									$ 103	$ (6,060)	$ (259)
Less:
Net income from continuing operations attributable to noncontrolling interests	$ 62	$ 0	$ (6)	$ 11	$ (12)	$ 26	$ (12)	$ 26	67	28	500
Net income (loss) attributable to AIG common shareholders from continuing operations									36	(6,088)	(759)
Income (loss) from discontinued operations, net of income tax expense	$ (2)	$ (39)	$ 0	$ (1)	$ (3)	$ (1)	$ 8	$ 0	(42)	4	(90)
Net income (loss) attributable to AIG common shareholders									$ (6)	$ (6,084)	$ (849)
Denominator for EPS:
Weighted average shares outstanding - basic	887,508,718	895,237,359	903,215,488	907,951,597	908,115,499	908,667,044	925,751,084	980,777,243	898,405,537	930,561,286	1,091,085,131
Dilutive shares									11,735,705	0	0
Weighted average shares outstanding - diluted	887,508,718	895,237,359	916,572,481	925,266,577	908,115,499	908,667,044	948,248,771	1,005,315,030	910,141,242	930,561,286	1,091,085,131
Basic:
Income (loss) from continuing operations	$ (0.7)	$ (1.37)	$ 1.04	$ 1.03	$ (7.33)	$ (1.91)	$ 1.21	$ 1.21	$ 0.04	$ (6.54)	$ (0.7)
Income (loss) from discontinued operations	(0.7)	(0.04)	0	0	0	0	0.01	0	(0.05)	0	(0.08)
Net income (loss) attributable to AIG									(0.01)	(6.54)	(0.78)
Diluted:
Income (loss) from continuing operations	(0.7)	(1.37)	1.02	1.01	(7.33)	(1.91)	1.18	1.18	0.04	(6.54)	(0.7)
Loss from discontinued operations	$ (0.7)	$ (0.04)	$ 0	$ 0	$ 0	$ 0	$ 0.01	$ 0	(0.05)	0	(0.08)
Net Income (loss) attributable to AIG									$ (0.01)	$ (6.54)	$ (0.78)
Number of shares, warrants, and options excluded from diluted shares outstanding because the effect would have been anti-dilutive									19,600,000	1,700,000	200,000
Dilutive Shares Excluded From Computation Of Diluted Earnings Per Share										22,412,682	30,326,772