Lease - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Sep. 09, 2020
Lessee Lease Description [Line Items]
Operating lease, extending Description	we leased the property pursuant to a master lease for a term extending through September 30, 2030, with two five-year extension
Operating lease, existence of option to extend [true false]	true
Right-of-use lease asset, net	$ 8,622,000	$ 8,841,000
Operating lease liability	8,643,000	$ 8,841,000
Lease costs	$ 327,000
Two Five Year Extensions [Member]
Lessee Lease Description [Line Items]
Operating lease, Renewal Term	5 years