Note 5 - Revenue From Contracts With Customers - Disaggregation of Revenues (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net revenues	$ 21,144	$ 14,443	$ 62,520	$ 38,948
Semiconductor Market [Member]
Net revenues	13,656	7,387	42,653	19,256
Industrial Market [Member]
Net revenues	5,463	4,220	13,535	12,346
Defense/ Aerospace [Member]
Net revenues	778	2,015	3,175	4,919
Telecommunications Market [Member]
Net revenues	315	419	870	1,427
Other Multi Markets [Member]
Net revenues	932	402	2,287	1,000
Thermal Testing Products [Member]
Net revenues	5,284	3,632	14,126	11,482
Thermal Process [Member]
Net revenues	6,412	5,574	18,785	13,885
Semiconductor Production Test Products [Member]
Net revenues	7,951	3,604	25,224	9,093
Service and Other Products [Member]
Net revenues	1,497	1,633	4,385	4,488
End User [Member]
Net revenues	17,366	12,651	54,291	34,518
OEM and Integrators [Member]
Net revenues	$ 3,778	$ 1,792	$ 8,229	$ 4,430