Net Loss Per Share - Weighted Average Shares (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Numerator:      
Net Loss $ (42,330) $ (48,486) $ (167,700)
Denominator:      
Weighted average common shares outstanding, basic and diluted 82,314,577 80,271,848  
Net loss per share, basic and diluted $ (0.51) $ (0.60)