DERIVATIVES ACTIVITIES - Fair Value Hedges (Details) - Other revenue - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	$ (1,109)	$ 690	$ 768	$ 1,096
Gain (loss) on the hedged item in designated and qualifying fair value hedges	1,165	(700)	(650)	(1,115)
Hedge ineffectiveness recognized in earnings on designated and qualifying fair value hedges	(14)	(25)	(5)	(83)
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	70	15	123	64
Interest rate contracts
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	(450)	1,111	2,747	72
Gain (loss) on the hedged item in designated and qualifying fair value hedges	442	(1,113)	(2,701)	(115)
Hedge ineffectiveness recognized in earnings on designated and qualifying fair value hedges	(11)	(1)	48	(42)
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	3	(1)	(2)	(1)
Foreign exchange contracts
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	(602)	(311)	(2,360)	1,093
Gain (loss) on the hedged item in designated and qualifying fair value hedges	664	304	2,425	(1,081)
Hedge ineffectiveness recognized in earnings on designated and qualifying fair value hedges	(3)	(24)	(53)	(41)
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	65	17	118	53
Commodity and other contracts
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	(57)	(110)	381	(69)
Gain (loss) on the hedged item in designated and qualifying fair value hedges	59	109	(374)	81
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	$ 2	$ (1)	$ 7	$ 12