Note 5 - Revenue From Contracts With Customers - Disaggregation of Revenues (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenue	$ 32,663	$ 30,771	$ 97,140	$ 84,423
Semiconductor Market [Member]
Revenue	19,767	19,170	56,283	48,969
Industrial Market [Member]
Revenue	2,456	2,130	8,399	7,859
Automotive [Member]
Revenue	1,789	1,621	5,928	7,971
Life Sciences [Member]
Revenue	1,540	1,715	4,188	3,583
Defense/ Aerospace [Member]
Revenue	3,392	1,914	10,121	4,830
Security [Member]
Revenue	1,102	871	3,004	2,239
Other Multi Markets [Member]
Revenue	2,617	3,350	9,217	8,972
Thermal Testing Products [Member]
Revenue	4,742	5,836	16,734	16,844
Thermal Process [Member]
Revenue	12,809	11,026	34,503	27,990
Semiconductor Production Test Products [Member]
Revenue	8,573	7,770	25,432	20,409
Video Imaging [Member]
Revenue	2,376	2,447	7,458	6,692
Flying Probe and In-circuit Testers [Member]
Revenue	2,012	1,605	4,588	5,359
Service and Other Products [Member]
Revenue	2,151	2,087	8,425	7,129
End User [Member]
Revenue	21,139	21,548	64,720	60,785
OEM and Integrators [Member]
Revenue	$ 11,524	$ 9,223	$ 32,420	$ 23,638