Fair Value Measurements and Derivative Instruments (Derivative Instruments) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Total net derivative (liability) asset	$ (2,403)	$ 1,854
Total derivative assets
Derivative [Line Items]
Total net derivative (liability) asset	308	3,256
Total derivative liabilities
Derivative [Line Items]
Total net derivative (liability) asset	(2,711)	(1,402)
Foreign exchange contracts | Derivatives designated as hedging instruments | Other current assets and prepayments
Derivative [Line Items]
Total net derivative (liability) asset	46	207
Foreign exchange contracts | Derivatives designated as hedging instruments | Accounts payable and accrued liabilities
Derivative [Line Items]
Total net derivative (liability) asset	(214)	(56)
Foreign exchange contracts | Derivatives not designated as hedging instruments | Other current assets and prepayments
Derivative [Line Items]
Total net derivative (liability) asset	262	3,049
Foreign exchange contracts | Derivatives not designated as hedging instruments | Accounts payable and accrued liabilities
Derivative [Line Items]
Total net derivative (liability) asset	(892)	(1,346)
Interest rate swaps | Derivatives designated as hedging instruments | Other noncurrent liabilities
Derivative [Line Items]
Total net derivative (liability) asset	$ (1,605)	$ 0