Quarterly report pursuant to Section 13 or 15(d)

Equity Incentive Plan - Stock Option Activity (Details)

v3.19.2
Equity Incentive Plan - Stock Option Activity (Details) - $ / shares
6 Months Ended 12 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Dec. 31, 2017
Equity Incentive Plan        
Number of Options, Outstanding beginning of year 2,076,153 1,893,003 1,893,003  
Number of Options, Granted 750,000 275,500    
Number of Options, Forfeited   (1,500)    
Number of Options, Expired (48,737) (60,968)    
Number of Options, Outstanding at end of period 2,777,416 2,106,035 2,076,153 1,893,003
Number of Options, Exercisable at end of period 1,651,546 1,429,484    
Number of Options, Vested and expected to vest at end of period 2,777,416 2,106,035    
Weighted- Average Exercise Price, Outstanding at beginning of year $ 2.28 $ 2.49 $ 2.49  
Weighted- Average Exercise Price, Granted 0.48 0.57    
Weighted- Average Exercise Price, Forfeited   0.83    
Weighted- Average Exercise Price, Expired 1.08 0.80    
Weighted- Average Exercise Price, Outstanding at end of period 1.81 2.29 $ 2.28 $ 2.49
Weighted- Average Exercise Price, Exercisable at end of period 2.65 2.65    
Weighted- Average Exercise Price, Vested and expected to vest at end of period $ 1.81 $ 2.29    
Weighted-Average Contractual Life (In Years), Outstanding 7 years 1 month 6 days 4 years 7 months 28 days 6 years 6 months 4 days 5 years 4 months 24 days
Weighted-Average Contractual Life (In Years), Exercisable at end of period 5 years 7 months 13 days 3 years 11 months 12 days    
Weighted-Average Contractual Life (In Years), Vested and expected to vest at end of period 7 years 1 month 6 days 4 years 7 months 28 days