SECURITIZATIONS AND VARIABLE INTEREST ENTITIES - Collateralized Debt and Loan Obligations (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Collateralized debt obligations (CDOs)
Variable Interest Entity
Carrying value of retained interests	$ 7	$ 6
Carrying value of retained interests, impact of 10% adverse change in discount rate	(1)	(1)
Carrying value of retained interests, impact of 20% adverse change in discount rate	(1)	(2)
Collateralized loan obligations (CLOs)
Variable Interest Entity
Carrying value of retained interests	1,816	1,549
Carrying value of retained interests, impact of 10% adverse change in discount rate	(10)	(9)
Carrying value of retained interests, impact of 20% adverse change in discount rate	$ (20)	$ (18)
Minimum \| Collateralized debt obligations (CDOs)
Variable Interest Entity
Discount rate	44.90%	44.70%
Minimum \| Collateralized loan obligations (CLOs)
Variable Interest Entity
Discount rate	1.50%	1.40%
Maximum \| Collateralized debt obligations (CDOs)
Variable Interest Entity
Discount rate	49.40%	49.20%
Maximum \| Collateralized loan obligations (CLOs)
Variable Interest Entity
Discount rate	1.60%	5.00%

Discount rate which is used to value residual cash flows generated by financial assets of the securitization, asset-backed financing arrangement, or similar transfer for initial fair value measurement.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=d3e107207-111719

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- Definition

The carrying amount (fair value) as of the balance sheet date of the transferor's interests in transferred financial assets (typically securitized receivables, generally not involved in the collection of principal) following transfer of significant portions of such financial instruments to other parties. Such interests could be ancillary cash flows and interest-only strips.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=d3e107314-111719

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- Definition

The hypothetical financial impact of a 10 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=d3e107314-111719

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- Definition

The hypothetical financial impact of a 20 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=d3e107314-111719

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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