FEDERAL FUNDS, SECURITIES BORROWED, LOANED AND SUBJECT TO REPURCHASE AGREEMENTS - Repurchase Agreements (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Assets Sold under Agreements to Repurchase
Repurchase agreements	$ 198,866	$ 170,496
Securities lending agreements	13,173	15,958
Gross amounts of recognized liabilities	212,039	186,454
U.S. Treasury and federal agency securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	66,171	66,263
Securities lending agreements	0	0
Gross amounts of recognized liabilities	66,171	66,263
State and municipal securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	1,054	334
Securities lending agreements	0	0
Gross amounts of recognized liabilities	1,054	334
Foreign government
Assets Sold under Agreements to Repurchase
Repurchase agreements	77,916	52,988
Securities lending agreements	611	1,390
Gross amounts of recognized liabilities	78,527	54,378
Corporate bonds
Assets Sold under Agreements to Repurchase
Repurchase agreements	18,799	17,164
Securities lending agreements	586	630
Gross amounts of recognized liabilities	19,385	17,794
Equity securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	11,419	12,206
Securities lending agreements	11,330	13,913
Gross amounts of recognized liabilities	22,749	26,119
Mortgage-backed securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	14,980	11,421
Securities lending agreements	0	0
Gross amounts of recognized liabilities	14,980	11,421
Asset-backed securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	5,321	5,428
Securities lending agreements	0	0
Gross amounts of recognized liabilities	5,321	5,428
Other
Assets Sold under Agreements to Repurchase
Repurchase agreements	3,206	4,692
Securities lending agreements	646	25
Gross amounts of recognized liabilities	3,852	4,717
Open and overnight
Assets Sold under Agreements to Repurchase
Repurchase agreements	91,133	79,740
Securities lending agreements	9,948	10,813
Gross amounts of recognized liabilities	101,081	90,553
Up to 30 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	56,163	50,399
Securities lending agreements	644	2,169
Gross amounts of recognized liabilities	56,807	52,568
31–90 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	24,255	19,396
Securities lending agreements	1,709	2,044
Gross amounts of recognized liabilities	25,964	21,440
Greater than 90 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	27,315	20,961
Securities lending agreements	872	932
Gross amounts of recognized liabilities	$ 28,187	$ 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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