FEDERAL FUNDS, SECURITIES BORROWED, LOANED AND SUBJECT TO REPURCHASE AGREEMENTS - Repurchase Agreements (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Assets Sold under Agreements to Repurchase
Repurchase agreements	$ 213,562	$ 170,496
Securities lending agreements	15,614	15,958
Gross amounts of recognized liabilities	229,176	186,454
U.S. Treasury and federal agency securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	67,622	66,263
Securities lending agreements	0	0
Gross amounts of recognized liabilities	67,622	66,263
State and municipal securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	1,031	334
Securities lending agreements	5	0
Gross amounts of recognized liabilities	1,036	334
Foreign government
Assets Sold under Agreements to Repurchase
Repurchase agreements	92,113	52,988
Securities lending agreements	221	1,390
Gross amounts of recognized liabilities	92,334	54,378
Corporate bonds
Assets Sold under Agreements to Repurchase
Repurchase agreements	19,731	17,164
Securities lending agreements	472	630
Gross amounts of recognized liabilities	20,203	17,794
Equity securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	11,910	12,206
Securities lending agreements	14,301	13,913
Gross amounts of recognized liabilities	26,211	26,119
Mortgage-backed securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	12,590	11,421
Securities lending agreements	0	0
Gross amounts of recognized liabilities	12,590	11,421
Asset-backed securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	5,373	5,428
Securities lending agreements	0	0
Gross amounts of recognized liabilities	5,373	5,428
Other
Assets Sold under Agreements to Repurchase
Repurchase agreements	3,192	4,692
Securities lending agreements	615	25
Gross amounts of recognized liabilities	3,807	4,717
Open and overnight
Assets Sold under Agreements to Repurchase
Repurchase agreements	97,624	79,740
Securities lending agreements	11,980	10,813
Gross amounts of recognized liabilities	109,604	90,553
Up to 30 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	54,810	50,399
Securities lending agreements	342	2,169
Gross amounts of recognized liabilities	55,152	52,568
31–90 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	23,997	19,396
Securities lending agreements	2,070	2,044
Gross amounts of recognized liabilities	26,067	21,440
Greater than 90 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	37,131	20,961
Securities lending agreements	1,222	932
Gross amounts of recognized liabilities	$ 38,353	$ 21,893

Amount, before effects of master netting arrangements, of securities sold under agreements to repurchase and securities loaned.

No definition available.

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Amount, before effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226000-175313

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Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226000-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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