Note 19 - Segment Information - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended																12 Months Ended
	Dec. 31, 2021	[1]	Sep. 30, 2021	[2]	Jun. 30, 2021	[3]	Mar. 31, 2021	[4]	Dec. 31, 2020	[5]	Sep. 30, 2020	[6]	Jun. 30, 2020	[7]	Mar. 31, 2020	[8]	Dec. 31, 2021	Dec. 31, 2020
Net revenues	$ 22,358		$ 21,144		$ 21,820		$ 19,556		$ 14,875		$ 14,443		$ 13,275		$ 11,230		$ 84,878	$ 53,823
Depreciation/amortization																	2,106	1,863
Operating income (loss)																	8,459	(1,217)
Earnings (loss) before income tax expense (benefit)	236		2,532		3,056		2,578		(454)		433		183		(1,393)		8,402	(1,231)
Income tax expense (benefit)	(51)		357		447		366		(74)		(25)		13		(250)		1,119	(336)
Net earnings (loss)	$ 287		$ 2,175		$ 2,609		$ 2,212		$ (380)		$ 458		$ 170		$ (1,143)		7,283	(895)
Capital expenditures																	994	658
Corporate, Non-Segment [Member]
Depreciation/amortization																	40	27
Operating income (loss)																	(3,731)	(429)
Earnings (loss) before income tax expense (benefit)																	(3,728)	(460)
Income tax expense (benefit)																	(497)	(126)
Net earnings (loss)																	(3,231)	(334)
Capital expenditures																	53	3
Thermal Testing Products [Member] | Operating Segments [Member]
Net revenues																	52,369	40,209
Depreciation/amortization																	1,931	1,727
Operating income (loss)																	2,759	325
Earnings (loss) before income tax expense (benefit)																	2,698	306
Income tax expense (benefit)																	359	84
Net earnings (loss)																	2,339	222
Capital expenditures																	518	371
EMS [Member] | Operating Segments [Member]
Net revenues																	32,509	13,614
Depreciation/amortization																	135	109
Operating income (loss)																	9,431	(1,113)
Earnings (loss) before income tax expense (benefit)																	9,432	(1,077)
Income tax expense (benefit)																	1,257	(294)
Net earnings (loss)																	8,175	(783)
Capital expenditures																	$ 423	$ 284

[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.

[5] The quarter ended December 31, 2020 includes $1,078 of restructuring and other charges which are discussed in Note 5.

[6] The quarter ended September 30, 2020 includes $161 of restructuring and other charges which are discussed in Note 5.

[7] The quarter ended June 30, 2020 includes $38 of restructuring and other charges which are discussed in Note 5.

[8] The quarter ended March 31, 2020 includes $8 of restructuring and other charges which are discussed in Note 5.