Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 18,510	$ 18,208
Accumulated depreciation	(14,169)	(14,142)
Property and equipment, net	4,341	4,066
Building and Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,317	1,304
Furniture, Fixtures and Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,399	1,379
Plant and Machinery
Property Plant And Equipment [Line Items]
Property and equipment, gross	13,509	13,244
Purchased Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 2,285	$ 2,281