Fair Value Measurement (Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	$ 147,523	$ 107,494
Marketable securities	11,193	62,442
Derivatives	407	667
Interest rate swap contracts
Liabilities, Fair Value Disclosure [Abstract]
Derivatives	1,793	2,403
Foreign currency derivatives
Liabilities, Fair Value Disclosure [Abstract]
Derivatives	2,917	3,515
Level I
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	147,523	107,494
Marketable securities	11,193	62,442
Derivatives	0	0
Level I | Interest rate swap contracts
Liabilities, Fair Value Disclosure [Abstract]
Derivatives	0	0
Level I | Foreign currency derivatives
Liabilities, Fair Value Disclosure [Abstract]
Derivatives	0	0
Level II
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	0	0
Marketable securities	0	0
Derivatives	407	667
Level II | Interest rate swap contracts
Liabilities, Fair Value Disclosure [Abstract]
Derivatives	1,793	2,403
Level II | Foreign currency derivatives
Liabilities, Fair Value Disclosure [Abstract]
Derivatives	2,917	3,515
Level III
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	0	0
Marketable securities	0	0
Derivatives	0	0
Level III | Interest rate swap contracts
Liabilities, Fair Value Disclosure [Abstract]
Derivatives	0	0
Level III | Foreign currency derivatives
Liabilities, Fair Value Disclosure [Abstract]
Derivatives	$ 0	$ 0