CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) [Abstract]
Net loss	$ (4,104)	$ (6,771)	$ (10,978)	$ (17,700)
Other comprehensive income
Employee pension plan adjustments	162	220	323	441
Comprehensive loss	$ (3,942)	$ (6,551)	$ (10,655)	$ (17,259)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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