Quarterly report pursuant to Section 13 or 15(d)

Significant accounting policies (Details)

v2.4.0.8
Significant accounting policies (Details) (USD $)
6 Months Ended 12 Months Ended 6 Months Ended
Jun. 30, 2014
Jun. 30, 2013
Jun. 30, 2014
Accounts receivable [Member]
Customer concentration [Member]
item
Dec. 31, 2013
Accounts receivable [Member]
Customer concentration [Member]
item
Dec. 31, 2013
Accounts receivable [Member]
Customer concentration [Member]
Customer One [Member]
Dec. 31, 2013
Accounts receivable [Member]
Customer concentration [Member]
Customer Two [Member]
Jun. 30, 2014
Net sales [Member]
Customer concentration [Member]
item
Jun. 30, 2014
Net sales [Member]
Customer concentration [Member]
Customer One [Member]
Jun. 30, 2014
Net sales [Member]
Customer concentration [Member]
Customer Two [Member]
Cash, cash equivalents and short-term investments:                  
Cash and cash equivalent investment portfolio, percentage 9.00%                
Unrealized loss $ 46,000 $ 51,000              
Realized loss 117,000 28,000              
Management fees 12,000 7,000              
Accounts receivable:                  
Accounts receivable, net 36,000                
Allowance for uncollectable accounts $ 2,000                
Concentration Risk [Line Items]                  
Risk percentage         38.00% 62.00%   37.00% 63.00%
Number of customers     1 2     2    
Income (loss) per share:                  
Shares not included in the computation of EPS 5,251,000 5,844,000