LOANS - Corporate Troubled Debt Restructurings (Details) (Corporate, USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Financing receivable impaired
Carrying Value	$ 1	$ 44
TDRs involving changes in the amount and/or timing of principal payments	1	27
TDRs involving changes in the amount and/or timing of interest payments	0	17
TDRs involving changes in the amount and/or timing of both principal and interest payments	0	0
Period within which default occurred post-modification	1 year
Number of days past due, default status	60 days
Carrying Value	529	739
TDR in payment default	0	0
Commercial market loans
Financing receivable impaired
Number of days past due, default status	90 days
Commercial and industrial
Financing receivable impaired
Carrying Value	0	40
TDRs involving changes in the amount and/or timing of principal payments	0	23
TDRs involving changes in the amount and/or timing of interest payments	0	17
TDRs involving changes in the amount and/or timing of both principal and interest payments	0	0
Carrying Value	88	182
TDR in payment default	0	0
Financial institutions
Financing receivable impaired
Carrying Value	0	0
TDRs involving changes in the amount and/or timing of principal payments	0	0
TDRs involving changes in the amount and/or timing of interest payments	0	0
TDRs involving changes in the amount and/or timing of both principal and interest payments	0	0
Carrying Value	0	0
TDR in payment default	0	0
Mortgage and real estate
Financing receivable impaired
Carrying Value	1	4
TDRs involving changes in the amount and/or timing of principal payments	1	4
TDRs involving changes in the amount and/or timing of interest payments	0	0
TDRs involving changes in the amount and/or timing of both principal and interest payments	0	0
Carrying Value	105	147
TDR in payment default	0	0
Other
Financing receivable impaired
Carrying Value	0	0
TDRs involving changes in the amount and/or timing of principal payments	0	0
TDRs involving changes in the amount and/or timing of interest payments	0	0
TDRs involving changes in the amount and/or timing of both principal and interest payments	0	0
Carrying Value	336	410
TDR in payment default	$ 0	$ 0

This represents the period within which the payment default occurred after the loan modification.

No definition available.

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- Definition

The amount of the outstanding recorded investment related to financing receivables that were modified by troubled debt restructurings occurring during the period. The modification is involving changes in the amount and/or timing of interest payments.

+ References

No definition available.

+ Details

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- Definition

+ References

No definition available.

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- Definition

+ References

No definition available.

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- Definition

Represents the classified default number of days for which the loan is past due.

+ References

No definition available.

+ Details

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524

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