SECURITIES BORROWED, LOANED AND SUBJECT TO REPURCHASE AGREEMENTS - Repurchase Agreements (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Assets Sold under Agreements to Repurchase
Repurchase agreements	$ 513,172	$ 296,218
Securities lending agreements	32,622	33,269
Total	545,794	329,487
U.S. Treasury and federal agency securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	223,343	99,979
Securities lending agreements	461	106
Total	223,804	100,085
State and municipal
Assets Sold under Agreements to Repurchase
Repurchase agreements	447	1,911
Securities lending agreements	2	0
Total	449	1,911
Foreign government
Assets Sold under Agreements to Repurchase
Repurchase agreements	174,661	123,826
Securities lending agreements	118	13
Total	174,779	123,839
Corporate bonds
Assets Sold under Agreements to Repurchase
Repurchase agreements	12,403	14,308
Securities lending agreements	195	45
Total	12,598	14,353
Marketable equity securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	5,853	9,749
Securities lending agreements	31,574	33,096
Total	37,427	42,845
Mortgage-backed securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	85,014	36,225
Securities lending agreements	21	0
Total	85,035	36,225
Asset-backed securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	3,032	1,755
Securities lending agreements	178	0
Total	3,210	1,755
Other debt securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	8,419	8,465
Securities lending agreements	73	9
Total	8,492	8,474
Open and overnight
Assets Sold under Agreements to Repurchase
Repurchase agreements	289,907	138,710
Securities lending agreements	24,997	25,388
Total	314,904	164,098
Up to 30 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	134,870	86,819
Securities lending agreements	0	267
Total	134,870	87,086
31–90 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	35,639	25,119
Securities lending agreements	1,270	2,121
Total	36,909	27,240
Greater than 90 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	52,756	45,570
Securities lending agreements	6,355	5,493
Total	$ 59,111	$ 51,063