Revenue Recognition - Schedule of Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenue	$ 20,329	$ 15,350	$ 63,291	$ 39,837
Technology development
Disaggregation of Revenue [Line Items]
Revenue	1,461	2,040	5,629	5,275
Test, measurement and sensing systems
Disaggregation of Revenue [Line Items]
Revenue	18,253	12,987	56,255	34,023
Other
Disaggregation of Revenue [Line Items]
Revenue	615	323	1,407	539
Goods transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue	17,106	12,987	52,044	34,023
Goods/services transferred over time
Disaggregation of Revenue [Line Items]
Revenue	3,223	2,363	11,247	5,814
Fixed-price contracts
Disaggregation of Revenue [Line Items]
Revenue	19,745	14,717	60,882	37,667
Cost-type contracts
Disaggregation of Revenue [Line Items]
Revenue	584	633	2,409	2,170
Sales to the U.S. government
Disaggregation of Revenue [Line Items]
Revenue	2,713	2,599	7,629	6,119
U.S. direct commercial sales and other
Disaggregation of Revenue [Line Items]
Revenue	8,444	6,130	25,642	15,503
Foreign commercial sales & other
Disaggregation of Revenue [Line Items]
Revenue	9,172	6,621	30,020	18,215
United States
Disaggregation of Revenue [Line Items]
Revenue	11,555	8,729	33,670	21,622
Asia
Disaggregation of Revenue [Line Items]
Revenue	3,390	4,532	10,658	11,857
Europe
Disaggregation of Revenue [Line Items]
Revenue	3,628	1,694	12,114	5,261
Canada, Central and South America
Disaggregation of Revenue [Line Items]
Revenue	1,756	319	6,849	782
All Others
Disaggregation of Revenue [Line Items]
Revenue	$ 0	$ 76	$ 0	$ 315