Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Net income (loss)	$ 4,100	$ (18,600)
Net pension adjustments, net of tax:
Liability adjustments for defined benefit pension plans	(2,900)
Reclassification of adjustments for defined benefit plans recorded in net loss	400	1,400
Total net pension adjustments	(2,500)	1,400
Net foreign currency translation:
Unrealized foreign currency translation income	700	300
Total net foreign currency translation	700	300
Total other comprehensive income, net of tax	(1,800)	1,700
Comprehensive income (loss)	$ 2,300	$ (6,700)