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Inventory (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Inventory Disclosure [Abstract]
Allowance for inventory obsolescence	$ 19,000		$ 19,000
Raw materials - current	29,821,000		26,152,000
Raw materials - long term, net	3,997,000		3,980,000
Finished Goods	1,022,000		1,022,000
Work in process	4,656,000		3,800,000
Inventory, net	39,496,000		$ 34,954,000
Write-offs of obsolete inventory against allowance	$ 0	$ 0

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount of valuation reserve for inventory.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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