GOODWILL AND INTANGIBLE ASSETS (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Finite and indefinite-lived intangible assets.
Gross carrying amount of Intangible assets (excluding MSRs)	$ 15,130	$ 15,204
Accumulated amortization of Intangible assets (excluding MSRs)	9,673	9,507
Gross carrying amount of Mortgage servicing rights (MSRs)	2,203	1,942
Gross carrying amount of Intangible assets	17,333	17,146
Accumulated amortization of Intangible assets	9,673	9,507
Finite and indefinite-lived intangible assets:
Net carrying amount of Intangible assets (excluding MSRs), balance at beginning of period	5,697
Net carrying amount of MSRs, balance at beginning of period	1,942
Net carrying amount of Intangible assets, balance at beginning of period	7,639
Amortization	(204)
Impairments	(25)
FX and other	(11)
Net carrying amount of Intangible assets (excluding MSRs), balance at end of period	5,457
Net carrying amount of MSRs, balance at end of period	2,203
Net carrying amount of Intangible assets, balance at end of period	7,660
Purchased credit card relationships
Finite and indefinite-lived intangible assets.
Gross carrying amount of Intangible assets (excluding MSRs)	7,621	7,632
Accumulated amortization of Intangible assets (excluding MSRs)	5,813	5,726
Finite and indefinite-lived intangible assets:
Net carrying amount of Intangible assets (excluding MSRs), balance at beginning of period	1,906
Amortization	(95)
Impairments	(4)
FX and other	1
Net carrying amount of Intangible assets (excluding MSRs), balance at end of period	1,808
Core deposit intangibles
Finite and indefinite-lived intangible assets.
Gross carrying amount of Intangible assets (excluding MSRs)	1,283	1,315
Accumulated amortization of Intangible assets (excluding MSRs)	1,023	1,019
Finite and indefinite-lived intangible assets:
Net carrying amount of Intangible assets (excluding MSRs), balance at beginning of period	296
Amortization	(19)
Impairments	(21)
FX and other	4
Net carrying amount of Intangible assets (excluding MSRs), balance at end of period	260
Other customer relationships
Finite and indefinite-lived intangible assets.
Gross carrying amount of Intangible assets (excluding MSRs)	725	767
Accumulated amortization of Intangible assets (excluding MSRs)	378	380
Finite and indefinite-lived intangible assets:
Net carrying amount of Intangible assets (excluding MSRs), balance at beginning of period	387
Amortization	(9)
FX and other	(31)
Net carrying amount of Intangible assets (excluding MSRs), balance at end of period	347
Present value of future profits
Finite and indefinite-lived intangible assets.
Gross carrying amount of Intangible assets (excluding MSRs)	241	239
Accumulated amortization of Intangible assets (excluding MSRs)	140	135
Finite and indefinite-lived intangible assets:
Net carrying amount of Intangible assets (excluding MSRs), balance at beginning of period	104
Amortization	(3)
Net carrying amount of Intangible assets (excluding MSRs), balance at end of period	101
Other:
Finite and indefinite-lived intangible assets.
Gross carrying amount of Intangible assets (excluding MSRs)	4,739	4,764
Accumulated amortization of Intangible assets (excluding MSRs)	2,319	2,247
Finite and indefinite-lived intangible assets:
Net carrying amount of Intangible assets (excluding MSRs), balance at beginning of period	2,517
Amortization	(78)
FX and other	(19)
Net carrying amount of Intangible assets (excluding MSRs), balance at end of period	2,420
Indefinite-lived intangible assets
Finite and indefinite-lived intangible assets.
Gross carrying amount of Intangible assets (excluding MSRs)	521	487
Finite and indefinite-lived intangible assets:
Net carrying amount of Intangible assets (excluding MSRs), balance at beginning of period	487
FX and other	34
Net carrying amount of Intangible assets (excluding MSRs), balance at end of period	$ 521