Quarterly report pursuant to Section 13 or 15(d)

Note 10 - Stock-based Compensation (Details Textual)

v3.20.2
Note 10 - Stock-based Compensation (Details Textual) - USD ($)
$ in Millions
9 Months Ended
Jul. 10, 2020
Jul. 02, 2020
May 05, 2020
Mar. 10, 2020
Jun. 03, 2019
Sep. 30, 2020
Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Subscription Rate           17.50%  
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares (in shares)           15.6  
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)           4 years  
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)           10 years  
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount           $ 14.1  
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)           1 year 255 days  
Restricted Stock Units (RSUs) [Member]              
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)     120 days 90 days      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) 645,000 40,000   645,000 80,000 645,000 80,000
Restricted Stock Units (RSUs) [Member] | Share-based Payment Arrangement, Tranche One [Member]              
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)         90 days    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)         40,000    
Restricted Stock Units (RSUs) [Member] | Share-based Payment Arrangement, Tranche Two [Member]              
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)     1 year 30 days   1 year