INVENTORIES (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
INVENTORIES
Parts and raw materials	$ 39,901	$ 35,849
Work-in-process	7,563	6,951
Finished goods	12,626	10,585
Inventories	$ 60,090	$ 53,385

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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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