Note 3 - Acquisition of EMI Industries, LLC (Details Textual) - USD ($)		2 Months Ended	3 Months Ended		12 Months Ended
	Apr. 18, 2024	Jun. 30, 2024	Sep. 30, 2024	Sep. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2021
Payments to Acquire Businesses, Gross			$ 59,000	$ (0)
Line of Credit Facility, Maximum Borrowing Capacity							$ 100,000,000
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations, Net of Tax					$ 36,303,000	$ 38,798,000
Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity							$ 75,000,000
EMI Industries [Member]
Business Combination, Consideration Transferred	$ 50,000,000
Business Combination, Consideration Transferred, Liabilities Incurred	100,000
Payments to Acquire Businesses, Gross	49,900,000		$ 59,000
Business Acquisition, Transaction Costs	1,000,000
Business Combination, Acquired Receivables, Gross Contractual Amount	$ 11,900,000
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		$ 18,100,000
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual		$ 700,000
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations, Net of Tax					$ 36,300,000