Inventories (Details) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Classification of inventories [Abstract]
Raw materials	$ 1,586,000	$ 1,408,000
Work in process	1,498,000	1,306,000
Finished goods	998,000	924,000
Total Inventories, net	4,082,000	3,638,000
Inventory reserve for obsolescence	$ 2,838,000	$ 2,773,000