Quarterly report pursuant to Section 13 or 15(d)

Stock options and warrants (Schedule of Award Activity) (Details)

v3.5.0.2
Stock options and warrants (Schedule of Award Activity) (Details) - USD ($)
6 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Stock Incentive Plan [Member]    
Shares Underlying Options    
Outstanding, beginning 332,560  
Granted 227,000  
Exercised  
Forfeited (25,445) (24,742)
Outstanding, ending 534,115  
Exercisable 331,427  
Weighted Average Exercise Price    
Outstanding, beginning $ 35.36  
Granted 2.89  
Exercised  
Forfeited 36.30  
Outstanding, ending 21.55  
Exercisable $ 32.44  
Weighted Average Remaining Contractual Term    
Outstanding 8 years 1 month 6 days  
Exercisable 7 years 1 month 6 days  
Aggregate Intrinsic Value    
Outstanding $ 140,740  
Exercisable $ 23,870  
Nonqualified [Member]    
Shares Underlying Options    
Outstanding, beginning 432,003  
Granted  
Exercised  
Forfeited  
Outstanding, ending 432,003  
Weighted Average Exercise Price    
Outstanding, beginning $ 15.47  
Granted  
Exercised  
Forfeited  
Outstanding, ending $ 15.47  
Weighted Average Remaining Contractual Term    
Outstanding 1 year 9 months 18 days  
Aggregate Intrinsic Value    
Outstanding