Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Lessee Lease Description [Line Items]
Total rent expense	$ 0.3	$ 0.4
Lessee, Operating Lease, Existence of Option to Extend [true false]	true
Weighted average remaining operating lease term	2 years 9 months 18 days
Weighted average discount rate of operating lease	6.30%
Sublease rental income due in future under non-cancelable subleases	$ 1.6
Operating lease liabilities, cash paid	0.4
Sublease rental income	$ 0.0
Minimum
Lessee Lease Description [Line Items]
Remaining lease term	1 year
Maximum
Lessee Lease Description [Line Items]
Remaining lease term	5 years
Operating leases, options to extend leases term	5 years