Quarterly report pursuant to Section 13 or 15(d)

Note 12 - Summary of Stock Options (Details Textual)

v3.21.2
Note 12 - Summary of Stock Options (Details Textual) - USD ($)
$ / shares in Units, Pure in Thousands
1 Months Ended 3 Months Ended 9 Months Ended
Jan. 31, 2021
Sep. 30, 2021
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Sep. 30, 2021
Sep. 30, 2020
Jun. 30, 2021
May 31, 2021
Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)   3,195,742       3,195,742       986,399
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance (in dollars per share)   $ 7.52       $ 7.52       $ 19.10
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term (Year)           9 years 3 months 18 days        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)           2,251,000        
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate   0.00% 0.00%     0.00% 0.00%      
Share-based Payment Arrangement, Expense   $ 1,088,000 $ 642,000     $ 2,765,000 $ 2,009,000      
Restricted Stock Units (RSUs) [Member]                    
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total   1,436,000       $ 1,436,000        
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)           1 year 3 months        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)           2 years        
Share-based Payment Arrangement, Expense   272,000       $ 771,000        
Share-based Payment Arrangement, Option [Member]                    
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate           0.00%        
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total   $ 6,618,000       $ 6,618,000        
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)           2 years 11 months 12 days        
The 2006 Stock Option Plan [Member]                    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)   12       12        
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)   0       0        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance (in dollars per share)   $ 9,920.00       $ 9,920.00        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term (Year)           1 year 3 months 18 days        
The 2013 Plan [Member]                    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)   3,195,730       3,195,730        
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)   66,753       66,753        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance (in dollars per share)   $ 7.48       $ 7.48        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term (Year)           9 years 3 months 18 days        
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in shares) 307,705                  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) 1,758,951             3,940,136   1,451,246
The 2013 Plan [Member] | Employees and Nonemployees [Member]                    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)   30,400 55,000     2,251,000 101,800      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)   $ 1.60 $ 3.60     $ 1.75 $ 53.25      
The 2013 Plan [Member] | Restricted Stock Units (RSUs) [Member]                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)   679,000       679,000        
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)           0        
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares)   5,000       11,000        
The 2013 Plan [Member] | Restricted Stock Units (RSUs) [Member] | Employees and Board Members [Member]                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) 690,000                  
The 2013 Plan [Member] | Restricted Stock [Member]                    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)   228       228        
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)   0 0     0 0      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares)   4 15     6 43      
2017 Employee Stock Purchase Plan [Member]                    
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)   10,844 22 30 32          
Shares Issued, Price Per Share (in dollars per share)   $ 1.94 $ 4.44 $ 4.79 $ 5.86 $ 1.94 $ 4.44      
Common Stock, Capital Shares Reserved for Future Issuance (in shares)               500,378 400  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant During Offering Period (in shares)               2,000 2  
Employee Stock Ownership Plan (ESOP), Number of Suspense Shares (in shares)   489,156       489,156