FEDERAL FUNDS, SECURITIES BORROWED, LOANED AND SUBJECT TO REPURCHASE AGREEMENTS - Repurchase Agreements (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Assets Sold under Agreements to Repurchase
Repurchase agreements	$ 196,215	$ 188,040
Securities lending agreements	16,565	14,657
Gross amounts of recognized liabilities	212,780	202,697
U.S. Treasury and federal agency securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	78,972	67,005
Securities lending agreements	16	0
Gross amounts of recognized liabilities	78,988	67,005
State and municipal securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	414	403
Securities lending agreements	0	0
Gross amounts of recognized liabilities	414	403
Foreign government
Assets Sold under Agreements to Repurchase
Repurchase agreements	62,520	66,633
Securities lending agreements	499	789
Gross amounts of recognized liabilities	63,019	67,422
Corporate
Assets Sold under Agreements to Repurchase
Repurchase agreements	16,596	15,355
Securities lending agreements	1,220	1,085
Gross amounts of recognized liabilities	17,816	16,440
Equity securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	9,707	10,297
Securities lending agreements	14,802	12,484
Gross amounts of recognized liabilities	24,509	22,781
Mortgage-backed securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	18,712	19,913
Securities lending agreements	0	0
Gross amounts of recognized liabilities	18,712	19,913
Asset-backed securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	4,941	4,572
Securities lending agreements	0	0
Gross amounts of recognized liabilities	4,941	4,572
Other debt securities
Assets Sold under Agreements to Repurchase
Repurchase agreements	4,353	3,862
Securities lending agreements	28	299
Gross amounts of recognized liabilities	4,381	4,161
Open and overnight
Assets Sold under Agreements to Repurchase
Repurchase agreements	106,370	89,732
Securities lending agreements	12,199	9,096
Gross amounts of recognized liabilities	118,569	98,828
Up to 30 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	46,934	54,336
Securities lending agreements	785	1,823
Gross amounts of recognized liabilities	47,719	56,159
31–90 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	17,933	21,541
Securities lending agreements	1,506	2,324
Gross amounts of recognized liabilities	19,439	23,865
Greater than 90 days
Assets Sold under Agreements to Repurchase
Repurchase agreements	24,978	22,431
Securities lending agreements	2,075	1,414
Gross amounts of recognized liabilities	$ 27,053	$ 23,845

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

No definition available.

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+ References

No definition available.

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- Definition

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=51825145&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=51825145&loc=SL20226000-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Repurchase Agreement Accounted for as a Collateralized Borrowing
-URI http://asc.fasb.org/extlink&oid=49203159

Reference 3: 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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