Annual report pursuant to Section 13 and 15(d)

Stock-based compensation. (Details)

v3.21.1
Stock-based compensation. (Details) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Nov. 18, 2019
Nov. 07, 2019
Jul. 16, 2016
Jul. 14, 2016
Stock-based compensation. (Details) [Line Items]            
Intrinsic value of the options outstanding $ 262,000 $ 0        
Fair value common stock at vesting aggregate 1,639,000 $ 599,000        
Total compensation cost related to unvested awards $ 865,000          
Compensation cost weighted average period 1 year 135 days          
2006 Stock Incentive Plan [Member]            
Stock-based compensation. (Details) [Line Items]            
Shares authorized 1,715,000          
2016 Stock Incentive Plan [Member]            
Stock-based compensation. (Details) [Line Items]            
Shares authorized     7,400,000 5,650,000 1,150,000 3,650,000