Commitments and Contingencies - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2021
Commitments And Contingencies [Line Items]
Right-of-use asset	$ 53,000	$ 131,000	$ 600,000
Operating lease, short-term liability	$ 39,000	$ 155,000
Operating lease, weighted average discount rate	9.00%
Operating lease remaining term	2 months
Facility Leases [Member]
Commitments And Contingencies [Line Items]
Right-of-use liability			$ 500,000
Redwood City, California [Member]
Commitments And Contingencies [Line Items]
Operating lease, description	began in June 2021 and expires in May 2023.
Operating lease beginning date	2021-06
Operating lease, expiration	2023-05