Balance Sheet Information - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 34,687	$ 35,260
Less: Accumulated depreciation and amortization	(26,638)	(27,026)
Land	1,770	1,770
Property and equipment, net	9,819	10,004
Building [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	6,922	6,922
Computers and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	10,439	10,217
Manufacturing and Test Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	13,850	14,661
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	1,491	1,475
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	1,965	1,965
Motor Vehicles [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 20	$ 20