DERIVATIVES - Fair Value Hedges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Other revenue
Gain (loss) on fair value hedges
Gain (loss) on the hedging derivatives included in assessment of the effectiveness of fair value hedges	$ (1,941)	$ (890)	$ (2,985)	$ (1,446)
Gain (loss) on the hedged item in designated and qualifying fair value hedges	1,941	891	2,983	1,447
Net gain (loss) on the hedging derivatives excluded from assessment of the effectiveness of fair value hedges	86	121	213	63
Net interest income
Gain (loss) on fair value hedges
Gain (loss) on the hedging derivatives included in assessment of the effectiveness of fair value hedges	(1,855)	(747)	(8,238)	(4,228)
Gain (loss) on the hedged item in designated and qualifying fair value hedges	1,793	667	8,036	3,934
Net gain (loss) on the hedging derivatives excluded from assessment of the effectiveness of fair value hedges	0	0	(11)	(3)
Interest rate contracts (gross) | Other revenue
Gain (loss) on fair value hedges
Gain (loss) on the hedging derivatives included in assessment of the effectiveness of fair value hedges	0	0	0	0
Gain (loss) on the hedged item in designated and qualifying fair value hedges	0	0	0	0
Net gain (loss) on the hedging derivatives excluded from assessment of the effectiveness of fair value hedges	0	0	0	0
Interest rate contracts (gross) | Net interest income
Gain (loss) on fair value hedges
Gain (loss) on the hedging derivatives included in assessment of the effectiveness of fair value hedges	(1,855)	(747)	(8,238)	(4,228)
Gain (loss) on the hedged item in designated and qualifying fair value hedges	1,793	667	8,036	3,934
Net gain (loss) on the hedging derivatives excluded from assessment of the effectiveness of fair value hedges	0	0	(11)	(3)
Foreign exchange contracts (gross)
Gain (loss) on fair value hedges
Amount of cross currency basis included in AOCI	40	12	116	(14)
Foreign exchange contracts (gross) | Other revenue
Gain (loss) on fair value hedges
Gain (loss) on the hedging derivatives included in assessment of the effectiveness of fair value hedges	(964)	(724)	(2,623)	(714)
Gain (loss) on the hedged item in designated and qualifying fair value hedges	964	725	2,621	715
Net gain (loss) on the hedging derivatives excluded from assessment of the effectiveness of fair value hedges	79	79	183	96
Foreign exchange contracts (gross) | Net interest income
Gain (loss) on fair value hedges
Gain (loss) on the hedging derivatives included in assessment of the effectiveness of fair value hedges	0	0	0	0
Gain (loss) on the hedged item in designated and qualifying fair value hedges	0	0	0	0
Net gain (loss) on the hedging derivatives excluded from assessment of the effectiveness of fair value hedges	0	0	0	0
Commodity hedges | Other revenue
Gain (loss) on fair value hedges
Gain (loss) on the hedging derivatives included in assessment of the effectiveness of fair value hedges	(977)	(166)	(362)	(732)
Gain (loss) on the hedged item in designated and qualifying fair value hedges	977	166	362	732
Net gain (loss) on the hedging derivatives excluded from assessment of the effectiveness of fair value hedges	7	42	30	(33)
Commodity hedges | Net interest income
Gain (loss) on fair value hedges
Gain (loss) on the hedging derivatives included in assessment of the effectiveness of fair value hedges	0	0	0	0
Gain (loss) on the hedged item in designated and qualifying fair value hedges	0	0	0	0
Net gain (loss) on the hedging derivatives excluded from assessment of the effectiveness of fair value hedges	$ 0	$ 0	$ 0	$ 0