GOODWILL AND INTANGIBLE ASSETS - Changes in Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	$ 4,566
Acquisitions/ divestitures	(123)
Amortization	(169)
Impairments	(5)
FX and other	(25)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	4,244
Mortgage servicing rights (MSRs)	1,685c_MortgageServicingRightsMSR	1,845c_MortgageServicingRightsMSR
Net carrying amount of Intangible assets, balance at end of period	5,929	6,411
Indefinite-lived intangible assets
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	290
Acquisitions/ divestitures	0
Amortization	0
Impairments	0
FX and other	(9)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	281
Purchased credit card relationships
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	1,332
Acquisitions/ divestitures	0
Amortization	(68)
Impairments	0
FX and other	(1)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	1,263
Core deposit intangibles
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	132
Acquisitions/ divestitures	0
Amortization	(11)
Impairments	0
FX and other	(5)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	116
Other customer relationships
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	248
Acquisitions/ divestitures	(55)
Amortization	(6)
Impairments	0
FX and other	(4)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	183
Present value of future profits
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	79
Acquisitions/ divestitures	(68)
Amortization	(3)
Impairments	0
FX and other	(1)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	7
Other
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	2,485
Acquisitions/ divestitures	0
Amortization	(81)
Impairments	(5)
FX and other	(5)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	$ 2,394

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Sum of the carrying amounts of all intangible assets, excluding goodwill and excluding mortgage servicing rights, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Intangible Assets, Excluding Mortgage Servicing Rights Acquisitions (Divestitures)

+ References

No definition available.

+ Details

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- Definition

This element represents the aggregate amount of amortization of intangible assets excluding mortgage servicing rights (MSRs) during the period.

+ References

No definition available.

+ Details

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- Definition

This element represents the aggregate amount of impairment of intangible assets excluding mortgage servicing rights (MSRs) during the period.

+ References

No definition available.

+ Details

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- Definition

This element represents net changes to the recorded value of intangible assets excluding mortgage servicing rights (MSRs), due to foreign currency translation adjustments and purchase accounting adjustments.

+ References

No definition available.

+ Details

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- Definition

This element represents the sum of the carrying amounts of all intangible assets excluding goodwill but including mortgage servicing rights, as of the balance sheet date that is net of accumulated amortization and impairment charges.

+ References

No definition available.

+ Details

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- Definition

The amount of mortgage servicing rights (MSRs) as of the balance sheet date.

+ References

No definition available.

+ Details

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- Details

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