Financial Instruments (Details 5) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivatives	$ 357	$ (433)	$ 330	$ (209)
Gain (loss) recognized in earnings attributable to risk being hedged	(187)	21	(116)	(100)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Recognized in OCI	109	1,224	1,059	1,220
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	273	(58)	843	(91)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, (Ineffectiveness) and Amounts Excluded from Effectiveness Testing	4	(1)	10	(2)
Gains and (Losses) excluded from the assessment of hedge effectiveness for fair value hedges	0	0	0	0
Gains and (Losses) associated with underlying exposure that did not occur or was not expected to occur for cash flow hedges	0	0	0	0
Gain (loss) on fair value hedges ineffectiveness	1	2	(2)	2
Foreign exchange contracts \| Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Recognized in OCI	36	524	467	596
Foreign exchange contracts \| Derivative instruments in net investment hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Recognized in OCI	73	700	592	624
Cost of financing \| Interest rate contracts \| Derivative instruments in fair value hedging relationships
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income, recognized on derivative instruments in fair value hedges	125	16	145	129
Gain (loss) recognized in earnings attributable to risk being hedged	(99)	11	(63)	(53)
Interest expense \| Interest rate contracts \| Derivative instruments in fair value hedging relationships
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income, recognized on derivative instruments in fair value hedges	112	15	121	116
Gain (loss) recognized in earnings attributable to risk being hedged	(88)	10	(53)	(47)
Interest expense \| Interest rate contracts \| Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	0	(1)	0	(1)
Interest expense \| Foreign exchange contracts \| Derivative instruments in net investment hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, (Ineffectiveness) and Amounts Excluded from Effectiveness Testing	4	0	6	(1)
Other (income) and expense \| Interest rate contracts \| Derivative instruments not designated as hedging instruments
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivatives	0	(3)	(2)	37
Other (income) and expense \| Foreign exchange contracts \| Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	185	(57)	565	(33)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, (Ineffectiveness) and Amounts Excluded from Effectiveness Testing	0	(1)	4	(1)
Other (income) and expense \| Foreign exchange contracts \| Derivative instruments not designated as hedging instruments
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivatives	208	(452)	134	(533)
Other (income) and expense \| Equity contracts \| Derivative instruments not designated as hedging instruments
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivatives	(8)	5	(5)	3
Cost of sales \| Foreign exchange contracts \| Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	46	(4)	154	(53)
SG&A expense \| Foreign exchange contracts \| Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	43	3	124	(5)
SG&A expense \| Equity contracts \| Derivative instruments not designated as hedging instruments
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivatives	$ (81)	$ (14)	$ (63)	$ 39

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.

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

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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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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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.

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The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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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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