SECURITIES BORROWED, LOANED AND SUBJECT TO REPURCHASE AGREEMENTS - Repurchase Agreements (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	$ 313,917	$ 338,564
Deposits received for securities loaned	32,346	24,689
Total	346,263	363,253
U.S. Treasury and federal agency securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	106,286	112,437
Deposits received for securities loaned	0	0
Total	106,286	112,437
State and municipal securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	636	664
Deposits received for securities loaned	0	2
Total	636	666
Foreign government securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	118,501	130,017
Deposits received for securities loaned	1,909	194
Total	120,410	130,211
Corporate bonds
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	21,778	20,149
Deposits received for securities loaned	148	78
Total	21,926	20,227
Equity securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	22,651	21,497
Deposits received for securities loaned	30,136	24,149
Total	52,787	45,646
Mortgage-backed securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	36,336	45,566
Deposits received for securities loaned	0	0
Total	36,336	45,566
Asset-backed securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	2,501	3,307
Deposits received for securities loaned	0	0
Total	2,501	3,307
Other
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	5,228	4,927
Deposits received for securities loaned	153	266
Total	5,381	5,193
Open and overnight
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	154,646	160,754
Deposits received for securities loaned	22,498	17,038
Total	177,144	177,792
Up to 30 days
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	74,302	98,226
Deposits received for securities loaned	1,265	3
Total	75,567	98,229
31–90 days
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	39,859	41,679
Deposits received for securities loaned	2,730	2,770
Total	42,589	44,449
Greater than 90 days
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	45,110	37,905
Deposits received for securities loaned	5,853	4,878
Total	$ 50,963	$ 42,783

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- Definition

Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a financial asset repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same financial asset at a date certain for a specified price. Includes repurchase-to-maturity transactions and liabilities not subject to a master netting arrangement.

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- Definition

Amount, before effects of master netting arrangements, of financial assets loaned to entities in exchange for collateral and funds outstanding borrowed in the form of a financial asset repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same financial assets at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
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-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Publisher FASB
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Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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