FAIR VALUE ELECTIONS - Certain Structured and Non-Structed Liabilities (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 22,600,000,000c_CertainStructuredLiabilities	$ 23,100,000,000c_CertainStructuredLiabilities
Excluding Consolidated VIE's
Certain non-structured liabilities
Aggregate unpaid principal balance in excess of (less than) fair value	(268,000,000)	(151,000,000)
Long-term debt \| Carrying amount \| Excluding Consolidated VIE's
Certain non-structured liabilities
Carrying amount reported on the Consolidated Balance Sheet	25,409,000,000	26,180,000,000
Short-term borrowings
Certain non-structured liabilities
Aggregate unpaid principal balance in excess of (less than) fair value	(10,000,000)	31,000,000
Short-term borrowings \| Carrying amount
Certain non-structured liabilities
Carrying amount reported on the Consolidated Balance Sheet	926,000,000	1,496,000,000
Interest Rate Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	10,100,000,000	10,900,000,000
Foreign Exchange Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	300,000,000	300,000,000
Equity Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	8,400,000,000	8,000,000,000
Commodity Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	1,600,000,000	1,400,000,000
Credit Linked
Carrying value of structured notes, disaggregated by type of embedded derivative instrument
Carrying value of structured notes	$ 2,200,000,000	$ 2,500,000,000

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No definition available.

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of short-term debt instruments that have contractual principal amounts and for which the fair value option has been elected.

+ References

No definition available.

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of long-term debt instruments that have contractual principal amounts and for which the fair value option has been elected.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 28

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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