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Organization - Additional Information (Detail)
$ / shares in Units, $ in Millions
1 Months Ended 12 Months Ended
Aug. 31, 2019
USD ($)
$ / shares
shares
Dec. 31, 2019
segment
Subsidiary, Sale of Stock [Line Items]    
Number of operating segments | segment   1
Public Stock Offering And Over-Allotment Option    
Subsidiary, Sale of Stock [Line Items]    
Payments of stock issuance costs $ 14.2  
Total proceeds from stock offering 244.5  
Payments of stock issuance costs, portion accrued 0.6  
Total proceeds from stock offering, net of offering expenses accrued $ 243.9  
Public Stock Offering    
Subsidiary, Sale of Stock [Line Items]    
Shares sold in offering (in shares) | shares 9,241,072  
Offering price per share (in dollars per share) | $ / shares $ 28.00  
Over-Allotment Option    
Subsidiary, Sale of Stock [Line Items]    
Shares sold in offering (in shares) | shares 1,205,357