GOODWILL AND INTANGIBLE ASSETS - Changes in Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	$ 5,056
Acquisitions/ divestitures	273
Amortization	(756)
Impairments	(2)
FX and other	(5)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	4,566
Mortgage servicing rights (MSRs)	1,845c_MortgageServicingRightsMSR	2,718c_MortgageServicingRightsMSR
Net carrying amount of Intangible assets, balance at end of period	6,411	7,774
Purchased credit card relationships
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	1,546
Acquisitions/ divestitures	110
Amortization	(324)
FX and other	0
Net carrying amount of Intangible assets (excluding MSRs), ending balance	1,332
Core deposit intangibles
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	203
Acquisitions/ divestitures	(6)
Amortization	(59)
FX and other	(6)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	132
Other customer relationships
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	286
Acquisitions/ divestitures	14
Amortization	(28)
FX and other	(24)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	248
Present value of future profits
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	92
Amortization	(12)
FX and other	(1)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	79
Other
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	2,606
Acquisitions/ divestitures	157
Amortization	(333)
Impairments	(2)
FX and other	57
Net carrying amount of Intangible assets (excluding MSRs), ending balance	2,485
Indefinite-lived intangible assets
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Net carrying amount of Intangible assets (excluding MSRs), beginning balance	323
Acquisitions/ divestitures	(2)
FX and other	(31)
Net carrying amount of Intangible assets (excluding MSRs), ending balance	$ 290

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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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- 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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