Annual report pursuant to Section 13 and 15(d)

Description of Business and Basis of Preparation - Additional Information (Detail)

v3.21.1
Description of Business and Basis of Preparation - Additional Information (Detail)
12 Months Ended
Jan. 08, 2021
USD ($)
Oct. 01, 2020
USD ($)
Jul. 17, 2020
shares
Jul. 16, 2020
shares
Dec. 31, 2020
USD ($)
shares
Dec. 31, 2019
USD ($)
shares
Jun. 18, 2019
shares
Jun. 17, 2019
shares
Dec. 31, 2018
shares
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]                  
Accumulated deficit         $ (326,613,000) $ (271,428,000)      
Cash and cash equivalents         93,041,000 $ 41,920,000      
Shelf registration maximum equity offering price         $ 437,000,000.0        
Reverse stock split, ratio       0.1          
Common stock, shares authorized (in shares) | shares     100,000,000 250,000,000 100,000,000 100,000,000 250,000,000 125,000,000  
Common stock, shares issued (in shares) | shares     10,508,302 105,083,291 19,663,698 9,741,372      
Common stock, shares outstanding (in shares) | shares     10,508,302 105,083,291 19,663,698 9,741,372      
Stock issued during period as result of reverse stock splits | shares     0 0          
Common Stock                  
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]                  
Common stock, shares outstanding (in shares) | shares         19,663,698 9,741,372     4,797,198
October 2020 Shelf Registration                  
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]                  
Shelf registration maximum equity initial offering price   $ 200,000,000.0              
October 2020 Shelf Registration | Sales Agreement | Common Stock                  
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]                  
Shelf registration maximum equity offering price   $ 50,000,000.0              
Subsequent Event | January 2021 Shelf Registration                  
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]                  
Shelf registration maximum equity initial offering price $ 200,000,000.0