Fair Value Measurements and Derivative Instruments (Derivative Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Total net derivative asset	$ 2,313	$ 1,854
Total derivative assets
Derivative [Line Items]
Total net derivative asset	6,071	3,256
Total derivative liabilities
Derivative [Line Items]
Total net derivative asset	(3,758)	(1,402)
Foreign exchange contracts | Derivatives designated as hedging instruments | Other current assets and prepayments
Derivative [Line Items]
Total net derivative asset	77	207
Foreign exchange contracts | Derivatives designated as hedging instruments | Accounts payable and accrued liabilities
Derivative [Line Items]
Total net derivative asset	(157)	(56)
Foreign exchange contracts | Derivatives not designated as hedging instruments | Other current assets and prepayments
Derivative [Line Items]
Total net derivative asset	5,994	3,049
Foreign exchange contracts | Derivatives not designated as hedging instruments | Accounts payable and accrued liabilities
Derivative [Line Items]
Total net derivative asset	$ (3,601)	$ (1,346)