DERIVATIVES - Effect of Customer Derivatives and Economic Hedges on Net Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative	$ 4		$ 36		$ 21		$ 67
Customer derivative contracts | Other Income | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative	2	[1]	55	[1]	151	[1]	(95)	[1]
Customer derivative contracts | Other Income | Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative	(60)	[1]	32	[1]	(54)	[1]	22	[1]
Customer derivative contracts | Mortgage Banking Fees | Residential loan commitments
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative	(4)	[2]	48	[2]	4	[2]	8	[2]
Economic hedges | Other Income | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative	5	[1]	(45)	[1]	(130)	[1]	133	[1]
Economic hedges | Foreign Exchange and Trade Finance Fees | Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative	59	[3]	(33)	[3]	52	[3]	(20)	[3]
Economic hedges | Mortgage Banking Fees | Forward sale contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative	$ 2	[2]	$ (21)	[2]	$ (2)	[2]	$ 19	[2]

[1] Reported in other income on the Consolidated Statements of Operations.

[2] Reported in mortgage banking fees on the Consolidated Statements of Operations.

[3] Reported in foreign exchange and trade finance fees on the Consolidated Statements of Operations.