Annual report pursuant to Section 13 and 15(d)

Stock-based Compensation - Narrative (Details)

v3.20.4
Stock-based Compensation - Narrative (Details)
$ / shares in Units, $ in Millions
1 Months Ended 3 Months Ended 12 Months Ended
Jun. 30, 2019
shares
Mar. 31, 2021
Mar. 31, 2020
Mar. 31, 2019
Dec. 31, 2020
USD ($)
installment
$ / shares
shares
Dec. 31, 2019
USD ($)
$ / shares
shares
Dec. 31, 2018
USD ($)
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Granted (shares) | shares         496,000 406,000 645,000
Weighted average grant date fair value (usd per share) | $ / shares         $ 6.03 $ 10.77 $ 5.34
Aggregate intrinsic value of options exercised         $ 1.8 $ 13.6 $ 7.6
Unrecognized compensation cost, options         $ 4.1    
Nonemployee Awards              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Granted (shares) | shares         76,000 0 0
Fair value of of options granted         $ 0.4    
Weighted average grant date fair value (usd per share) | $ / shares         $ 5.04    
2019 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Total shares remaining available for issuance (shares) | shares 7,897,144       6,800,000    
Shares reserved for future issuance (in shares) | shares 14,000,000            
Number of shares authorized (in shares) | shares 8,100,000            
Incentive Stock Options              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Option price as a percent of common stock         100.00%    
Non-Statutory Stock Options              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Option price as a percent of common stock         85.00%    
Stock options              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Percent of voting interests         10.00%    
Purchase price of common stock when voting percent is above minimum threshold         110.00%    
Expiration period         10 years    
Vesting period of units granted         4 years    
Weighted-average remaining amortization period (years)         2 years 4 months 24 days    
Stock options | Tranche One              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Vesting period of units granted         1 year    
Award vesting rights percentage         25.00%    
Stock options | Tranche Two              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Vesting period of units granted         3 years    
Award vesting rights percentage         75.00%    
RSUs              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Weighted-average remaining amortization period (years)         1 year 10 months 24 days    
Equity instruments other than options, aggregate intrinsic value, vested         $ 2.1 $ 4.1 $ 2.9
Unrecognized compensation cost, awards other than options         $ 1.4    
RSUs | Tranche One              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Vesting period of units granted         3 years    
Award vesting rights percentage 33.00%            
RSUs | Tranche Two              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Vesting period of units granted         4 years    
Award vesting rights percentage         25.00%    
PBOs              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Threshold level multiplier 0            
Estimated performance goal achievement rate     118.00%        
Weighted-average remaining amortization period (years)         6 months    
Unrecognized compensation cost, awards other than options         $ 1.1    
Exercises in period, intrinsic value         $ 0.0 1.3 0.2
PBOs | 2019 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of installments | installment         2    
PBOs | 2019 PSU and PBO Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Estimated performance goal achievement rate     84.00%        
PBOs | 2020 PSU and PBO Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Estimated performance goal achievement rate         88.00%    
PBOs | Tranche One | 2019 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Future vesting rights, percentage         50.00%    
PBOs | Tranche One | 2019 PSU and PBO Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Award vesting rights percentage     50.00%        
PBOs | Tranche One | 2018 PSU and PBO Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Award vesting rights percentage       50.00%      
PBOs | Tranche Two | 2019 Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Future vesting rights, percentage         50.00%    
PBOs | Tranche Two | 2019 PSU and PBO Plan | Forecast              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Award vesting rights percentage   50.00%          
PBOs | Tranche Two | 2018 PSU and PBO Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Award vesting rights percentage     50.00%        
RSAs              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Weighted-average remaining amortization period (years)         1 year 7 months 6 days    
Equity instruments other than options, aggregate intrinsic value, vested         $ 0.4 1.0 2.1
Unrecognized compensation cost, awards other than options         $ 0.6    
PSUs              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Weighted-average remaining amortization period (years)         7 months 6 days    
Equity instruments other than options, aggregate intrinsic value, vested         $ 1.3 $ 3.8 $ 5.4
Unrecognized compensation cost, awards other than options         $ 0.5