INVENTORIES (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
INVENTORIES
Parts and raw materials	$ 33,511	$ 34,449
Work-in-process	7,917	7,557
Finished goods	11,534	12,965
Inventories	$ 52,962	$ 54,971

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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