Leases - Additional Details of Leases Presented in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Right of use assets	$ 1,793	$ 2,263
Lease liabilities, current	$ 663	$ 663
Operating lease, liability, current, statement of financial position [Extensible list]	us-gaap:AccountsPayableAndOtherAccruedLiabilitiesCurrent	us-gaap:AccountsPayableAndOtherAccruedLiabilitiesCurrent
Lease liabilities, long-term	$ 1,772	$ 2,435
Operating lease, liability, noncurrent, statement of financial position [Extensible list]	us-gaap:LiabilitiesOtherThanLongtermDebtNoncurrent	us-gaap:LiabilitiesOtherThanLongtermDebtNoncurrent
Weighted-average remaining life	3 years 2 months 12 days	4 years 1 month 6 days
Weighted-average discount rate	8.20%	8.20%