DERIVATIVES ACTIVITIES - Fair Value Hedges (Details) (Other revenue, USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	$ 2,692	$ (3,023)	$ 499
Gain (loss) on the hedged item in designated and qualifying fair value hedges	(2,668)	3,019	(702)
Hedge ineffectiveness recognized in earnings on designated and qualifying fair value hedges	37	(88)	(233)
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	(13)	84	30
Interest rate contracts
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	1,546	(3,288)	122
Gain (loss) on the hedged item in designated and qualifying fair value hedges	(1,496)	3,204	(371)
Hedge ineffectiveness recognized in earnings on designated and qualifying fair value hedges	53	(84)	(249)
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	(3)	0	0
Foreign exchange contracts
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	1,367	265	377
Gain (loss) on the hedged item in designated and qualifying fair value hedges	(1,422)	(185)	(331)
Hedge ineffectiveness recognized in earnings on designated and qualifying fair value hedges	(16)	(4)	16
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	(39)	84	30
Commodity and other contract options
Gain (loss) on fair value hedges
Gain (loss) on the derivatives in designated and qualifying fair value hedges	(221)	0
Gain (loss) on the hedged item in designated and qualifying fair value hedges	250	0
Net gain (loss) excluded from assessment of the effectiveness of fair value hedges	$ 29	$ 0

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Net gain (loss) relating to components of the gain (loss) on the fair value hedging instrument excluded from the assessment of fair value hedge effectiveness. Recognized in earnings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

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