BUSINESS COMBINATION (Details - Narrative) $ in Millions		3 Months Ended		9 Months Ended
	Jul. 18, 2018 USD ($) shares	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 27, 2018 $ / shares	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Revenues		$ 11,486.0	$ 11,751.0	$ 34,829.0	$ 36,885.0
Net income (loss)		(1,259.0)	(1,713.0)	621.0	616.0
Net income (loss) attributable to AIG		(1,259.0)	$ (1,739.0)	616.0	$ 576.0
Other invested assets		19,739.0		19,739.0			$ 20,822.0
Validus Holdings, Ltd
Business Acquisition [Line Items]
Interest acquired	100.00%
Cash consideration paid	$ 5,475.0
Revenues		756.0		756.0
Net income (loss)		(105.0)		(105.0)
Net income (loss) attributable to AIG		(105.0)		(105.0)
Integration and transaction costs associated with acquired businesses		91.0		91.0
Redemption price of preference shares acquired | $ / shares						26,000
Goodwill	$ 1,997.0
Validus Holdings, Ltd | Series A [Member]
Business Acquisition [Line Items]
Number of preference shares acquired | shares	6,000
Dividend rate of preference shares acquired	5.875%
Validus Holdings, Ltd | Series B [Member]
Business Acquisition [Line Items]
Number of preference shares acquired | shares	10,000
Dividend rate of preference shares acquired	5.80%
Validus Holdings, Ltd | North America
Business Acquisition [Line Items]
Goodwill	$ 1,800.0
Validus Holdings, Ltd | International
Business Acquisition [Line Items]
Goodwill	$ 157.0
AlphaCat [Member]
Business Acquisition [Line Items]
Other invested assets		$ 128.0		$ 128.0