Leases - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($) Agreement
Lessee Lease Description [Line Items]
Average age of property	15 years 6 months
Right-of-use asset	$ 1.7	$ 0.4
Operating lease liability	$ 1.9	$ 0.4
Number of lease agreement | Agreement		2
Operating Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesMember	us-gaap:OtherLiabilitiesMember
California [Member] | San Diego [Member] | Lease
Lessee Lease Description [Line Items]
Operating lease agreement expire date	2022-04
Washington, D.C. [Member] | Lease
Lessee Lease Description [Line Items]
Operating lease agreement expire date	2026-08