SECURITIES BORROWED, LOANED AND SUBJECT TO REPURCHASE AGREEMENTS - Repurchase Agreements (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	$ 292,529	$ 338,564
Deposits received for securities loaned	39,779	24,689
Total	332,308	363,253
U.S. Treasury and federal agency securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	106,277	112,437
Deposits received for securities loaned	0	0
Total	106,277	112,437
State and municipal securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	700	664
Deposits received for securities loaned	0	2
Total	700	666
Foreign government securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	106,812	130,017
Deposits received for securities loaned	204	194
Total	107,016	130,211
Corporate bonds
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	22,993	20,149
Deposits received for securities loaned	265	78
Total	23,258	20,227
Equity securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	26,227	21,497
Deposits received for securities loaned	39,113	24,149
Total	65,340	45,646
Mortgage-backed securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	23,699	45,566
Deposits received for securities loaned	0	0
Total	23,699	45,566
Asset-backed securities
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	2,052	3,307
Deposits received for securities loaned	0	0
Total	2,052	3,307
Other
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	3,769	4,927
Deposits received for securities loaned	197	266
Total	3,966	5,193
Open and overnight
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	138,514	160,754
Deposits received for securities loaned	29,519	17,038
Total	168,033	177,792
Up to 30 days
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	75,384	98,226
Deposits received for securities loaned	1,058	3
Total	76,442	98,229
31–90 days
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	31,346	41,679
Deposits received for securities loaned	1,677	2,770
Total	33,023	44,449
Greater than 90 days
Assets Sold under Agreements to Repurchase
Securities sold under agreements to repurchase	47,285	37,905
Deposits received for securities loaned	7,525	4,878
Total	$ 54,810	$ 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
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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