Inventories (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Classification of inventories [Abstract]
Inventory reserve for obsolescence	$ 1,213,000	$ 2,773,000
Inventory wrote off	1,254,000
Inventory net realizable value	0
Raw materials	1,526,000	1,408,000
Work in process	1,337,000	1,306,000
Finished goods	1,012,000	924,000
Total Inventories, net	$ 3,875,000	$ 3,638,000