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Note 12 - Goodwill and Other Intangible Assets (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Aug. 31, 2025	Aug. 01, 2025
Goodwill	$ 1,258	$ 736
Finite-Lived Intangible Assets, Net	5,155	1,649
Impairment of Intangible Assets, Finite-Lived	0	2,761
Amortization of Intangible Assets	218	395
Intelligent Industrial [Member]
Goodwill	500
Finite-Lived Intangible Assets, Net	3,700
Smart Water [Member]
Goodwill	700
Finite-Lived Intangible Assets, Net	400
Energy Solutions [Member]
Finite-Lived Intangible Assets, Net	$ 1,100
Oil and Gas Markets [Member]
Impairment of Intangible Assets, Finite-Lived		$ 2,800
Geovox [Member]
Goodwill			$ 500	$ 500
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill			$ 3,700	$ 3,700