Derivatives - Amount of Gain (Loss) Recognized in OCI and Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) recognized in OCI	$ (207)	$ 667	$ (3,938)	$ 3,541
Derivatives designated as cash flow hedges \| Interest rate swap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) recognized in OCI	(186)	664	(2,855)	3,532
Derivatives designated as cash flow hedges \| Interest rate swap \| Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) recognized in income	(3,415)	(2,329)	(9,295)	(8,064)
Amount of Gain/(Loss) reclassified from AOCI	520		1,716
Amount of Gain/(Loss) reclassified from AOCI		428		998
Derivatives designated as cash flow hedges \| Foreign currency forward contract
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) recognized in OCI	505	543	555	1,112
Derivatives designated as cash flow hedges \| Foreign currency forward contract \| Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) recognized in income	243,049	221,659	736,930	649,504
Amount of Gain/(Loss) reclassified from AOCI	118		220
Amount of Gain/(Loss) reclassified from AOCI		86		(299)
Derivatives designated as cash flow hedges \| Foreign currency forward contract \| Cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) recognized in income	(138,913)	(119,620)	(416,194)	(359,400)
Amount of Gain/(Loss) reclassified from AOCI	$ (112)		$ (298)
Amount of Gain/(Loss) reclassified from AOCI		$ 26		$ 404

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount, before tax and after reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness, attributable to parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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