SEGMENT DATA Long Lived Assets (Details) - USD ($) $ in Thousands		Jun. 30, 2018		Dec. 31, 2017		Jun. 30, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Long-lived assets		$ 96,781	[1]	$ 103,648	[1]	$ 95,659	$ 89,080
Bulgaria
Segment Reporting Information [Line Items]
Long-lived assets		8,005		7,863
Czech Republic
Segment Reporting Information [Line Items]
Long-lived assets		39,978		46,146
Romania
Segment Reporting Information [Line Items]
Long-lived assets		28,680		28,515
Slovak Republic
Segment Reporting Information [Line Items]
Long-lived assets		17,415		17,450
Total operating segments
Segment Reporting Information [Line Items]
Long-lived assets	[1]	94,078		99,974
Corporate
Segment Reporting Information [Line Items]
Long-lived assets		$ 2,703		$ 3,674

[1] (1) Reflects property, plant and equipment, net