Leases - Additional Information (Detail)	1 Months Ended			3 Months Ended
	May 31, 2020 USD ($) Option	Mar. 31, 2020 USD ($) Option	Jan. 31, 2020	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Jun. 30, 2020 USD ($)
Lessee Lease Description [Line Items]
Operating lease right-of-use assets				$ 5,949,000		$ 6,334,000
Operating leases, liability				7,298,000		7,700,000
Long-term operating lease liabilities				$ 5,196,000		$ 5,638,000
Weighted-average discount rate				5.50%		5.50%
Weighted-average remaining lease term				3 years 9 months 18 days		4 years 1 month 6 days
Total cash paid for amounts included in the measurement of lease liabilities				$ 500,000	$ 200,000
ROU assets obtained in exchange for operating lease liabilities				0	2,200,000
Total operating lease rent expense				500,000	300,000
ASC 842
Lessee Lease Description [Line Items]
Total operating lease rent expense				$ 500,000	200,000
San Diego Lease
Lessee Lease Description [Line Items]
Lease commencement date			May 31, 2020
Lease commencement amendment date	Aug. 01, 2020
Lease extended expiration date	Nov. 30, 2025
Operating lease, existence of option to extend	true
Description of operating lease, option to extend	a one-time option to extend for a period of five additional years.
Number of options to extend lease | Option	1
Lease agreement additional extended lease term	5 years
Lease, monthly minimum rent payable	$ 58,000
Operating lease rate of increase in annual rent	3.00%
Lease allowance	$ 1,000,000.0
Operating lease right-of-use assets		$ 2,200,000			2,200,000
Operating leases, liability		$ 2,200,000			$ 2,200,000
Boston Lease
Lessee Lease Description [Line Items]
Lease commencement date		Apr. 01, 2020
Operating lease, existence of option to extend		true
Description of operating lease, option to extend		one-time option to extend the Boston Lease for a period of five additional years after the expiration of the initial lease term
Number of options to extend lease | Option		1
Lease agreement additional extended lease term		5 years			5 years
Lease, monthly minimum rent payable		$ 105,500
Operating lease rate of increase in annual rent		2.00%
Operating lease right-of-use assets							$ 5,100,000
Operating leases, liability							$ 5,100,000
Lease expiration date		Jul. 31, 2024
Boston Lease | Letter of Credit
Lessee Lease Description [Line Items]
Letter of Credit		$ 200,000			$ 200,000
Sublease
Lessee Lease Description [Line Items]
Operating lease rate of increase in annual rent	5.00%
Operating lease right-of-use assets	$ 300,000
Operating leases, liability	$ 300,000
Sublease commencement date	Jun. 09, 2020
Sublease term	2 years
Sublease | One Year
Lessee Lease Description [Line Items]
Lease, monthly minimum rent payable	$ 12,500