Derivative Instruments - Schedule of Derivative Assets and Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Derivative [Line Items]
Total net derivative asset (liability)	$ 24	$ (29)
Derivative instruments designated as hedges
Derivative [Line Items]
Total net derivative asset (liability)	14	(19)
Derivative instruments not designated as hedges
Derivative [Line Items]
Total net derivative asset (liability)	10	(10)
Prepaid expenses and other current assets \| Foreign exchange contracts \| Derivative instruments designated as hedges
Derivative [Line Items]
Derivative asset, fair value	16	0
Prepaid expenses and other current assets \| Foreign exchange contracts \| Derivative instruments not designated as hedges
Derivative [Line Items]
Derivative asset, fair value	1	0
Accrued liabilities \| Foreign exchange contracts \| Derivative instruments designated as hedges
Derivative [Line Items]
Derivative liability, fair value	0	(9)
Accrued liabilities \| Foreign exchange contracts \| Derivative instruments not designated as hedges
Derivative [Line Items]
Derivative liability, fair value	0	(2)
Accrued liabilities \| Forward interest rate swaps \| Derivative instruments designated as hedges
Derivative [Line Items]
Derivative liability, fair value	(1)	(2)
Accrued liabilities \| Forward interest rate swaps \| Derivative instruments not designated as hedges
Derivative [Line Items]
Derivative liability, fair value	(3)	(1)
Other long-term assets \| Forward interest rate swaps \| Derivative instruments not designated as hedges
Derivative [Line Items]
Derivative asset, fair value	12	0
Other long-term liabilities \| Forward interest rate swaps \| Derivative instruments designated as hedges
Derivative [Line Items]
Derivative liability, fair value	(1)	(8)
Other long-term liabilities \| Forward interest rate swaps \| Derivative instruments not designated as hedges
Derivative [Line Items]
Derivative liability, fair value	$ 0	$ (7)

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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