Note 5 - Goodwill and Other Intangible Assets, Net - Goodwill By Reportable Segment (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Beginning Balance	$ 16,453,049	$ 16,231,938
Acquisitions	1,330,987	0
Adjustments	0	221,111
Ending Balance	17,784,036	16,453,049
Commercial Air Handling [Member]
Beginning Balance	478,256	478,256
Acquisitions	0	0
Adjustments	0	0
Ending Balance	478,256	478,256
Industrial and Transportation Products [Member]
Beginning Balance	15,974,793	15,753,682
Acquisitions	1,330,987	0
Adjustments	0	221,111
Ending Balance	$ 17,305,780	$ 15,974,793