SECURITIES BORROWED, LOANED AND SUBJECT TO REPURCHASE AGREEMENTS - Offsetting (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Securities purchased under agreements to resell
Gross amounts of recognized assets	$ 281,274	$ 246,788
Gross amounts offset on the Consolidated Balance Sheet	111,400	87,424
Net amounts of assets included on the Consolidated Balance Sheet	169,874	159,364
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	134,150	124,557
Net amounts	35,724	34,807
Deposits paid for securities borrowed
Gross amounts of recognized assets	90,047	111,320
Gross amounts offset on the Consolidated Balance Sheet	8,599	0
Net amounts of assets included on the Consolidated Balance Sheet	81,448	111,320
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	27,067	35,766
Net amounts	54,381	75,554
Total
Total	371,321	358,108
Gross amounts offset on the Consolidated Balance Sheet	119,999	87,424
Net amounts of assets included on the Consolidated Balance Sheet	251,322	270,684
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	161,217	160,323
Net amounts	90,105	110,361
Securities sold under agreements to repurchase
Gross amounts of recognized liabilities	266,564	253,514
Gross amounts offset on the Consolidated Balance Sheet	111,400	87,424
Net amounts of liabilities included on the Consolidated Balance Sheet	155,164	166,090
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	91,034	82,823
Net amounts	64,130	83,267
Deposits received for securities loaned
Gross amounts of recognized liabilities	19,774	11,678
Gross amounts offset on the Consolidated Balance Sheet	8,599	0
Net amounts of liabilities included on the Consolidated Balance Sheet	11,175	11,678
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	3,138	3,415
Net amounts	8,037	8,263
Total
Gross amounts of recognized liabilities	286,338	265,192
Gross amounts offset on the Consolidated Balance Sheet	119,999	87,424
Net amounts of liabilities included on the Consolidated Balance Sheet	166,339	177,768
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	94,172	86,238
Net amounts	$ 72,167	$ 91,530