Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Mar. 01, 2020
Operating Leased Assets [Line Items]
Lease commencement date	Mar. 01, 2020
Lease expiration date	Aug. 31, 2031
Lessee, operating lease, existence of option to extend	false
Rent abatement term	6 months
Right-of-use asset	$ 4,491	$ 4,411	$ 4,500
Operating lease liability	$ 4,920		$ 4,500
Security deposit		$ 77
Operating lease remaining term	10 years 4 months 24 days
Finance lease remaining term	3 years
Operating lease weighted-average discount rate	12.20%
Finance lease weighted-average discount rate	10.00%
Conatus Pharmaceuticals Inc [Member]
Operating Leased Assets [Line Items]
Right-of-use asset	$ 100
Operating lease liability	$ 200
Office Space [Member]
Operating Leased Assets [Line Items]
Lease expiration date	Sep. 30, 2020
Letter of Credit [Member]
Operating Leased Assets [Line Items]
Security deposit	$ 300
Maximum [Member]
Operating Leased Assets [Line Items]
Tenant improvement allowance on modified lease	$ 2,200