Annual report pursuant to Section 13 and 15(d)

Stock-Based Payments - Stock Options (Details)

v3.20.4
Stock-Based Payments - Stock Options (Details) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Unrecognized compensation costs $ 10,600,000    
Period in which compensation costs will be recognized 2 years 5 months 8 days    
Granted and outstanding (in shares) 1,195,050    
Intrinsic value of options exercised $ 800,000 $ 200,000 $ 1,400,000
Cash received from option exercises 1,100,000 200,000 $ 600,000
Performance-based stock options      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Additional stock-based compensation expense recorded related to achievement of certain performance-based milestones 400,000 $ 400,000  
Unrecognized compensation costs 0    
Performance-based stock options | Advisor      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Unrecognized compensation costs $ 300,000    
Period in which compensation costs will be recognized 5 years 8 months 12 days    
Granted and outstanding (in shares) 75,000