Balance Sheet Information - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 38,424	$ 38,297
Less: Accumulated depreciation and amortization	(28,704)	(28,118)
Land	1,770	1,770
Property and equipment, net	11,490	11,949
Building [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	6,922	6,892
Computers and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	10,474	10,604
Manufacturing and Test Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	16,536	16,305
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	1,460	1,455
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	3,012	3,021
Motor Vehicles [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 20	$ 20