REVENUE RECOGNITION - Disaggregation of Revenue (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) segment	Sep. 30, 2019 USD ($)
Reconciliation of disaggregated revenue to segment revenue as well as revenue by geographical regions
Number of reportable segment | segment			1
Revenues	$ 94,653	$ 96,633	$ 273,696	$ 283,159
United States
Reconciliation of disaggregated revenue to segment revenue as well as revenue by geographical regions
Revenues	56,185	64,739	159,862	186,697
Europe
Reconciliation of disaggregated revenue to segment revenue as well as revenue by geographical regions
Revenues	31,800	31,448	93,944	95,010
Other
Reconciliation of disaggregated revenue to segment revenue as well as revenue by geographical regions
Revenues	6,668	446	19,890	1,452
Vehicle
Reconciliation of disaggregated revenue to segment revenue as well as revenue by geographical regions
Revenues	32,378	33,001	79,017	97,375
Industrial
Reconciliation of disaggregated revenue to segment revenue as well as revenue by geographical regions
Revenues	25,307	30,572	86,882	94,076
Medical
Reconciliation of disaggregated revenue to segment revenue as well as revenue by geographical regions
Revenues	23,448	14,550	62,260	39,180
Aerospace & Defense
Reconciliation of disaggregated revenue to segment revenue as well as revenue by geographical regions
Revenues	8,844	12,621	30,503	36,018
Other
Reconciliation of disaggregated revenue to segment revenue as well as revenue by geographical regions
Revenues	$ 4,676	$ 5,889	$ 15,034	$ 16,510