Note 5 - Revenue From Contracts With Customers - Disaggregation of Revenues (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenue	$ 32,558	$ 29,571	$ 64,477	$ 53,652
Semiconductor Market [Member]
Revenue	18,833	16,409	36,516	29,799
Industrial Market [Member]
Revenue	2,806	2,930	5,943	5,729
Automotive [Member]
Revenue	1,542	3,594	4,139	6,350
Defense/ Aerospace [Member]
Revenue	3,890	1,423	6,729	2,916
Life Sciences [Member]
Revenue	1,135	1,169	2,648	1,868
Security [Member]
Revenue	936	794	1,902	1,368
Other Multi Markets [Member]
Revenue	3,416	3,252	6,600	5,622
Thermal Testing Products [Member]
Revenue	6,172	5,951	11,993	11,008
Thermal Process [Member]
Revenue	11,872	9,968	21,694	16,964
Semiconductor Production Test Products [Member]
Revenue	8,753	6,632	16,859	12,639
Video Imaging [Member]
Revenue	2,434	2,395	5,082	4,245
Flying Probe and In-circuit Testers [Member]
Revenue	1,417	2,088	2,576	3,777
Service and Other Products [Member]
Revenue	1,910	2,537	6,273	5,019
End User [Member]
Revenue	21,877	22,095	43,581	39,237
OEM and Integrators [Member]
Revenue	$ 10,681	$ 7,476	$ 20,896	$ 14,415