Note 3 - Sale of Subsidiary (Details Textual) - USD ($)		12 Months Ended
	Aug. 30, 2024	Sep. 30, 2024	Sep. 30, 2023
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal		$ (14,539,000)	$ 0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax		(13,083,000)	(0)
Financing Receivable, Allowance for Credit Loss		900,000	$ (0)
Discontinued Operations, Disposed of by Sale [Member] | Subsidiary, Oil and Gas Product Manufacturing Operations in the Russian Federation [Member]
Disposal Group, Including Discontinued Operation, Consideration	$ 1,000,000
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax	(13,100,000)
Accounts and Financing Receivable, after Allowance for Credit Loss		$ 3,600,000
Discontinued Operations, Disposed of by Sale [Member] | Subsidiary, Oil and Gas Product Manufacturing Operations in the Russian Federation [Member] | Subsidiaries [Member]
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	(14,500,000)
Discontinued Operations, Disposed of by Sale [Member] | Subsidiary, Oil and Gas Product Manufacturing Operations in the Russian Federation [Member] | Promissory Notes [Member]
Disposal Group, Including Discontinued Operation, Consideration	$ 3,500,000
Notes Receivable, Term (Year)	10 years
Notes Receivable, Interest Rate, Stated Percentage	5.00%
Notes Receivable, Periodic Payment	$ 37,000
Financing Receivable, Allowance for Credit Loss	$ 900,000