Derivative Instruments - Impact on Statements of Income, Fair Value Hedges (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Gains/(losses) recorded in income
Derivatives	$ 10,434	$ (4,080)	$ (6,795)
Hedged items	(9,188)	4,411	5,935
Total income statement impact	1,246	331	(860)
Income statement impact due to:
Hedge ineffectiveness	173	(94)	79
Excluded components	1,073	425	(939)
Interest rate contracts
Gains/(losses) recorded in income
Derivatives	2,106	(3,469)	(1,238)
Hedged items	(801)	4,851	1,879
Total income statement impact	1,305	1,382	641
Income statement impact due to:
Hedge ineffectiveness	131	(132)	(28)
Excluded components	1,174	1,514	669
Foreign exchange contracts
Gains/(losses) recorded in income
Derivatives	8,279	(1,096)	(3,027)
Hedged items	(8,532)	864	2,925
Total income statement impact	(253)	(232)	(102)
Income statement impact due to:
Hedge ineffectiveness	0	0	0
Excluded components	(253)	(232)	(102)
Commodity contracts
Gains/(losses) recorded in income
Derivatives	49	485	(2,530)
Hedged items	145	(1,304)	1,131
Total income statement impact	194	(819)	(1,399)
Income statement impact due to:
Hedge ineffectiveness	42	38	107
Excluded components	$ 152	$ (857)	$ (1,506)

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)

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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)

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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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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

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