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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Financing Arrangements and Derivative Financial Instruments - Fair Values for Foreign Currency Contracts (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures
Foreign currency derivatives, notional amount	$ 2,576		$ 2,576		$ 1,409
Foreign currency derivatives, net transaction gains (losses)	7	$ (10)	52	$ (55)
Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures
Foreign currency derivatives, notional amount	273		273		250
Accounts receivable
Derivative Instruments and Hedging Activities Disclosures
Fair value - asset, not designated as hedging instruments	22		22		3
Fair value - asset, designated as hedging instruments	6		6		1
Other current liabilities
Derivative Instruments and Hedging Activities Disclosures
Fair value - liability, not designated as hedging instruments	(3)		(3)		(9)
Fair value - liability, designated as hedging instruments	(2)		(2)		(8)
Other assets
Derivative Instruments and Hedging Activities Disclosures
Fair value - asset, designated as hedging instruments	2		2		0
Other long term liabilities
Derivative Instruments and Hedging Activities Disclosures
Fair value - liability, designated as hedging instruments	$ 0		$ 0		$ (2)