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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Note 6 - Fair Value of Financial Instruments (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Aug. 31, 2025	Aug. 01, 2025	Aug. 30, 2024
Financing Receivable, before Allowance for Credit Loss	$ 24,451	$ 12,996
Financing Receivable, Allowance for Credit Loss	914	900
Impairment of Intangible Assets, Finite-Lived	0	2,761
Geovox [Member]
Business Combination, Contingent Consideration, Liability	2,540	$ 0	$ 2,500	$ 2,500
Business Combination, Contingent Consideration, Range of Outcomes, Maximum, Amount			$ 3,300	$ 3,300
Emerging Markets [Member]
Impairment of Intangible Assets, Finite-Lived	$ 2,800
Promissory Note [Member] \| Subsidiary, Oil and Gas Product Manufacturing Operations in the Russian Federation [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Financing Receivable, before Allowance for Credit Loss					$ 3,500
Financing Receivable, Allowance for Credit Loss					900
Promissory Note [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Nonrecurring [Member] \| Subsidiary, Oil and Gas Product Manufacturing Operations in the Russian Federation [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Financing Receivable, before Allowance for Credit Loss					3,500
Financing Receivable, Allowance for Credit Loss					$ 900