Financial Instruments (Net investment hedges in foreign operations) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Net investment hedges in foreign operation
Hedge ineffectiveness gain (loss)	$ (77)	$ (74)
Net Investment Hedge [Member]
Net investment hedges in foreign operation
Hedge ineffectiveness gain (loss)	(549)	(678)
Foreign Exchange Contract [Member] \| Net Investment Hedge [Member]
Net investment hedges in foreign operation
Gain (loss) recognized in AOCI	5,741	2,322
Gain (loss) reclassified from AOCI into earnings	$ 88	$ (1,525)

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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

-Publisher FASB

-Name Accounting Standards Codification

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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Amount of gain (loss) from the ineffectiveness of the hedge.

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

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