Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Additional Information (Detail)

v3.21.2
Stock-Based Compensation - Additional Information (Detail) - USD ($)
1 Months Ended 3 Months Ended
Jan. 31, 2021
Dec. 31, 2019
Jun. 30, 2021
Jun. 30, 2020
Apr. 01, 2021
Mar. 31, 2021
Dec. 18, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of common shares available for future issuance (in shares)     14,782,804   3,918,850 10,875,718  
Common shares reserved for grant (in shares)     7,128,692     1,781,043  
Weighted average fair value at the grant date (in dollars per share)     $ 7.77 $ 13.11      
Share based compensation expense     $ 3,820,000 $ 3,918,000      
Research and Development Expense              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Share based compensation expense     37,000 419,000      
Incentive Stock Options              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Unrecognized equity-based compensation related to unvested stock options     $ 45,200,000        
Remaining weighted average service period for recognition     2 years 9 months        
Restricted stock units (vested and not settled and unvested)              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Restricted stock units, outstanding (in shares)     931,923     1,095,676  
Unrecognized equity-based compensation related to RSUs     $ 14,100,000        
Remaining weighted average service period for recognition     2 years 4 months 17 days        
Restricted stock units, grants in period (in shares)     152,474        
Restricted stock (unvested)              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Restricted stock units, outstanding (in shares)     868,323        
Restricted stock units vested and not settled (not unvested)              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Restricted stock units outstanding (in shares)     63,600        
Roivant Sciences Ltd. (RSL) | Research and Development Expense              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Share based compensation expense     $ 100,000 $ 100,000      
Roivant Sciences Ltd. (RSL) | Restricted stock units (vested and not settled and unvested)              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Unrecognized equity-based compensation related to unvested stock options     1,000,000.0        
Share based compensation expense     $ 0        
Restricted stock units, grants in period (in shares) 25,000            
Award requisite service period 8 years            
2019 Equity Incentive Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of common shares available for future issuance (in shares)   5,500,000 7,128,692        
Maximum number of shares issued (in shares)   16,500,000          
Percentage of common stock outstanding   4.00%          
Common shares reserved for grant (in shares)     3,506,449        
2019 Equity Incentive Plan | Restricted stock units (vested and not settled and unvested)              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Restricted stock units, outstanding (in shares)     931,923        
2018 Equity Incentive Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Common shares reserved for grant (in shares)     3,205,740        
Options outstanding (in shares)             4,408,287