Note 19 - Segment Information - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	[1]	Sep. 30, 2021	[2]	Jun. 30, 2021	[3]	Mar. 31, 2021	[4]	Dec. 31, 2022	Dec. 31, 2021
Net revenues	$ 32,405	$ 30,771	$ 29,571	$ 24,081	$ 22,358		$ 21,144		$ 21,820		$ 19,556		$ 116,828	$ 84,878
Earnings before income tax expense	$ 3,881	$ 3,039	$ 2,570	$ 655	$ 236		$ 2,532		$ 3,056		$ 2,578		10,145	8,402
Acquired intangible amortization													(2,694)	(1,440)
Other income (expense)													(576)	(57)
Operating Segments [Member]
Net revenues													116,828	84,878
Earnings before income tax expense													21,978	18,981
Operating Segments [Member] | Electronic Test [Member]
Net revenues													40,219	32,509
Earnings before income tax expense													9,931	10,926
Operating Segments [Member] | Environmental Technologies [Member]
Net revenues													30,172	26,896
Earnings before income tax expense													3,817	4,236
Operating Segments [Member] | Process Technologies [Member]
Net revenues													46,437	25,473
Earnings before income tax expense													8,230	3,819
Corporate, Non-Segment [Member]
Earnings before income tax expense													$ (8,563)	$ (9,082)

[1] The quarter ended December 31, 2021 includes a recovery of $17 of restructuring and other charges which are discussed in Note 5.

[2] The quarter ended September 30, 2021 includes $51 of restructuring and other charges which are discussed in Note 5.

[3] The quarter ended June 30, 2021 includes $197 of restructuring and other charges which are discussed in Note 5.

[4] The quarter ended March 31, 2021 includes $55 of restructuring and other charges which are discussed in Note 5.