CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) [Abstract]
Net income (loss)	$ 1,340	$ (600)	$ (7,192)	$ (11,578)
Other comprehensive income
Employee pension plan adjustments	154	162	462	485
Comprehensive income (loss)	$ 1,494	$ (438)	$ (6,730)	$ (11,093)

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

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