Quarterly report pursuant to Section 13 or 15(d)

Description of business and summary of significant accounting policies - Additional Information (Details)

v3.5.0.2
Description of business and summary of significant accounting policies - Additional Information (Details)
3 Months Ended 6 Months Ended
Jun. 30, 2016
USD ($)
Jun. 30, 2015
USD ($)
Mar. 31, 2015
USD ($)
Jun. 30, 2016
USD ($)
segment
Jun. 30, 2015
USD ($)
Dec. 31, 2015
USD ($)
Debt Instrument [Line Items]            
Number of Operating Segments | segment       1    
Revenues, Bill And Hold       $ 2,186,698 $ 0  
Recovery from previously recorded loss $ 89,000          
Loss on Contracts   $ 0 $ 155,000 66,000 $ 0  
Allowance for Doubtful Accounts Receivable, Current 44,000     44,000   $ 50,000
Inventory Valuation Reserves $ 253,000     $ 253,000   $ 293,000