SECURITIES BORROWED, LOANED AND SUBJECT TO REPURCHASE AGREEMENTS - Offsetting (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Securities purchased under agreements to resell
Gross amounts of recognized assets	$ 315,360	$ 281,274
Gross amounts offset on the Consolidated Balance Sheet	133,473	111,400
Net amounts of assets included on the Consolidated Balance Sheet	181,887	169,874
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	145,631	134,150
Net amounts	36,256	35,724
Deposits paid for securities borrowed
Gross amounts of recognized assets	105,098	90,047
Gross amounts offset on the Consolidated Balance Sheet	4,061	8,599
Net amounts of assets included on the Consolidated Balance Sheet	101,037	81,448
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	28,174	27,067
Net amounts	72,863	54,381
Total
Gross amounts of recognized assets	420,458	371,321
Gross amounts offset on the Consolidated Balance Sheet	137,534	119,999
Net amounts of assets included on the Consolidated Balance Sheet	282,924	251,322
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	173,805	161,217
Net amounts	109,119	90,105
Securities sold under agreements to repurchase
Gross amounts of recognized liabilities	337,292	266,564
Gross amounts offset on the Consolidated Balance Sheet	133,473	111,400
Net amounts of liabilities included on the Consolidated Balance Sheet	203,819	155,164
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	116,042	91,034
Net amounts	87,777	64,130
Deposits received for securities loaned
Gross amounts of recognized liabilities	15,964	19,774
Gross amounts offset on the Consolidated Balance Sheet	4,061	8,599
Net amounts of liabilities included on the Consolidated Balance Sheet	11,903	11,175
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	3,475	3,138
Net amounts	8,428	8,037
Total
Gross amounts of recognized liabilities	353,256	286,338
Gross amounts offset on the Consolidated Balance Sheet	137,534	119,999
Net amounts of liabilities included on the Consolidated Balance Sheet	215,722	166,339
Amounts not offset on the Consolidated Balance Sheet but eligible for offsetting upon counterparty default	119,517	94,172
Net amounts	$ 96,205	$ 72,167