Product Line and Geographic Information - Result of Product Line Revenues and Gross Profits (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Results of operations by segments
Revenues	$ 22,542	$ 17,707
Gross Profit	$ 9,333	$ 8,338
Gross Profit %	41.40%	47.10%
Operating Segments [Member] | Antennas & Industrial IoT Devices [Member]
Results of operations by segments
Revenues	$ 17,102	$ 11,723
Gross Profit	$ 5,247	$ 3,747
Gross Profit %	30.70%	32.00%
Operating Segments [Member] | Test & Measurement Products [Member]
Results of operations by segments
Revenues	$ 5,583	$ 6,205
Gross Profit	$ 4,162	$ 4,588
Gross Profit %	74.50%	73.90%
Corporate, Non-Segment [Member]
Results of operations by segments
Revenues	$ (143)	$ (221)
Gross Profit	$ (76)	$ 3