Summary of Warranty Accrual Activity (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Balance at beginning of period	$ 407	$ 316
Warranty accrual acquired in acquisition		90
Accruals for warranties charged to expense	55	19
Cost of warranty claims	(141)	(18)
Balance at end of period	$ 321	$ 407