Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 7,177	$ 13,195	$ 18,307	$ 23,048
Other comprehensive income (loss):
Foreign currency exchange translation adjustments	233	(5,304)	338	(3,834)
Minimum pension liability, net of tax	1,739	(593)	1,089	(932)
Derivative Instrument	(17)	0	322	0
Other comprehensive income (loss)	1,955	(5,897)	1,749	(4,766)
Comprehensive income	$ 9,132	$ 7,298	$ 20,056	$ 18,282

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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