ACCRUED EXPENSES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
ACCRUED EXPENSES [Abstract]
Sales commissions	$ 2,461	$ 2,066
Subcontracting labor	1,408	1,370
Salaries, bonuses and related benefits	16,531	17,587
Warranty accrual	1,769	2,718
Other	8,339	7,808
Accrued expenses	30,508	31,549
Warranty Accrual Activity Account [Roll Forward]
Balance, beginning of year	2,718	3,659
Charges and costs accrued	268	761
Adjustments related to pre-existing warranties (including changes in estimates)	(969)	(1,063)
Less: Repair costs incurred	(311)	(544)
Currency translation	63	(95)
Balance, end of year	$ 1,769	$ 2,718