Derivatives - Cash Flow Hedges (Details) - Cash flow hedge - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Jun. 30, 2014	Mar. 31, 2014	Feb. 29, 2016
Derivatives in Cash Flow Hedging Relationships
Maximum length of time hedged in cash flow hedge	36 months		24 months	12 months
Pretax Gain (Loss) Recognized in Other Comprehensive Income on Effective portion of Derivative	$ (121)	$ 136
Accumulated other comprehensive income (loss), unrealized gain (loss) on cash flow hedges	14
After-tax net unrealized gain (loss) anticipated to be reclassifed from AOCI to the income statement within next twelve months	36
After-tax net unrealized gain (loss) anticipated to be reclassifed from AOCI to the Income Statement over remaining fiscal year	38
After-tax net unrealized gain (loss) anticipated to be reclassifed from AOCI to the Income Statement in 2017	(9)
After-tax unrealized gain (loss) anticipated to be reclassifed from AOCI to the Income Statement after 2017	(15)
Gain (Loss) on Hedged Item Recognized in Income	52	27
Foreign currency forward/option contracts
Derivatives in Cash Flow Hedging Relationships
Pretax Gain (Loss) Recognized in Other Comprehensive Income on Effective portion of Derivative	(120)	136
Foreign currency forward/option contracts | Cost of sales
Derivatives in Cash Flow Hedging Relationships
Gain (Loss) on Hedged Item Recognized in Income	53	30
Interest rate swap contracts
Derivatives in Cash Flow Hedging Relationships
Derivative notional amount					$ 100
Pretax Gain (Loss) Recognized in Other Comprehensive Income on Effective portion of Derivative	(1)
Accumulated other comprehensive income (loss), unrealized gain (loss) on cash flow hedges	(5)
Interest rate swap contracts | Interest expense
Derivatives in Cash Flow Hedging Relationships
Gain (Loss) on Hedged Item Recognized in Income	$ (1)	(1)
Commodity price swap contracts | Cost of sales
Derivatives in Cash Flow Hedging Relationships
Gain (Loss) on Hedged Item Recognized in Income		$ (2)