DERIVATIVES ACTIVITIES - Fair Value Hedges (Details) - Other revenue - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	$ (385)	$ 1,103
Gain (loss) on the hedged item in designated and qualifying fair value hedges	491	(1,127)
Hedge ineffectiveness recognized in earnings on designated and qualifying fair value hedges	52	(48)
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	54	24
Interest rate contracts
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	(305)	2,115
Gain (loss) on the hedged item in designated and qualifying fair value hedges	296	(2,090)
Hedge ineffectiveness recognized in earnings on designated and qualifying fair value hedges	(10)	27
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	1	(2)
Foreign exchange contracts
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	(82)	(1,361)
Gain (loss) on the hedged item in designated and qualifying fair value hedges	196	1,307
Hedge ineffectiveness recognized in earnings on designated and qualifying fair value hedges	62	(75)
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	52	21
Commodity and other contracts
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	2	349
Gain (loss) on the hedged item in designated and qualifying fair value hedges	(1)	(344)
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	$ 1	$ 5