Nature of the Business - Additional Information (Detail) - USD ($)	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Accumulated deficit	$ (249,943,000)	$ (238,323,000)
Aggregate principal amount of initial loan advance	11,301,000
Cash, cash equivalents and marketable securities	39,800,000
Hercules Loan Agreement [Member] | Tranche 1 Advance [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Aggregate principal amount of initial loan advance	12,500,000		$ 12,500,000
Hercules Loan Agreement [Member] | Maximum [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Aggregate principal amount of initial loan advance	30,000,000.0		$ 30,000,000.0
Minimum qualified cash balance	10,000,000.0
Hercules Loan Agreement [Member] | Minimum [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Minimum qualified cash balance	$ 6,300,000