Derivative Instruments and Hedging Activities - Income Statement Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Foreign currency forward contracts \| Net revenue \| Cash flow hedge
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Deferred Gain/(Loss) Recognized in Other Comprehensive (Loss)/Income	$ 1,209	$ 33,641	$ 10,327	$ 15,803
Amount of Net Gain/(Loss) Reclassified from Accumulated Other Comprehensive Loss into Net Income	6,493	(8,064)	9,712	(18,948)
Foreign currency forward contracts \| Cost of revenue \| Cash flow hedge
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Deferred Gain/(Loss) Recognized in Other Comprehensive (Loss)/Income	382	(8,813)	6,460	4,658
Amount of Net Gain/(Loss) Reclassified from Accumulated Other Comprehensive Loss into Net Income	941	2,662	1,069	1,836
Foreign currency forward contracts \| Other, net \| Cash flow hedge
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Deferred Gain/(Loss) Recognized in Other Comprehensive (Loss)/Income			0	0
Amount of Net Gain/(Loss) Reclassified from Accumulated Other Comprehensive Loss into Net Income			0	(1,376)
Foreign currency forward contracts \| Other, net \| Not designated
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss)/Gain Recognized in Net Income	1,039	5,776	1,517	826
Commodity forward contracts \| Other, net \| Not designated
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss)/Gain Recognized in Net Income	$ (102)	$ (1,426)	$ 1,021	$ (4,621)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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