Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance		$ 368,255
Other comprehensive income (loss)		3,428	$ (5,473)	$ 8,790
Amounts reclassified from accumulated other comprehensive loss	[1]	986	826	1,045
Ending Balance		417,172	368,255
Total Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance		(22,527)	(17,880)	(27,715)
Ending Balance		(18,113)	(22,527)	(17,880)
Cumulative Translation Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance		(12,485)	(8,313)	(17,222)
Other comprehensive income (loss)		3,267	(4,172)	8,909
Ending Balance		(9,218)	(12,485)	(8,313)
Pension Liability Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance		(10,042)	(9,567)	(10,493)
Other comprehensive income (loss)		161	(1,301)	(119)
Amounts reclassified from accumulated other comprehensive loss	[1]	986	826	1,045
Ending Balance		$ (8,895)	$ (10,042)	$ (9,567)

[1] The amounts reclassified from accumulated other comprehensive loss were included in other income (expense) in the consolidated statements of operations.