Accrued Warranty - (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Accrued Warranty
Balance beginning of period	$ 338	$ 228
Accrued warranty expense	54	431
Warranty claims paid	(163)	(324)
Transferred in sale of DuraFit	(110)	0
Translation adjustment	6	3
Balance end of period	$ 125	$ 338
Minimum
Accrued Warranty [Line Items]
Product warranty accrual warranty period	1 year
Maximum
Accrued Warranty [Line Items]
Product warranty accrual warranty period	5 years