Inventories, net (Details) - USD ($) $ in Thousands  | 
Mar. 31, 2019  | 
Dec. 31, 2018  | 
|---|---|---|
| Inventory Disclosure [Abstract] | ||
| Raw materials | $ 2,967 | $ 2,676 | 
| Work in progress | 303 | 331 | 
| Finished goods | 335 | 730 | 
| Inventory | 3,605 | 3,737 | 
| Less: inventory reserve | (305) | (366) | 
| Inventories, net | $ 3,300 | $ 3,371 | 
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- References No definition available. 
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- Definition Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of valuation reserve for inventory. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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