CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 5,095	$ (12,497)	$ 13,585	$ (37,091)
Other comprehensive income (loss):
Foreign currency exchange translation adjustments	1,488	1,920	(584)	(2,885)
Minimum pension liability, net of tax	387	(446)	673	(893)
Derivative instrument, net of tax	(77)	1,104	(503)	(1,674)
Other comprehensive income (loss)	1,798	2,578	(414)	(5,452)
Comprehensive income (loss)	$ 6,893	$ (9,919)	$ 13,171	$ (42,543)