Note 5 - Debt (Details Textual) $ in Thousands			3 Months Ended		6 Months Ended
	Nov. 18, 2020 USD ($)	Jan. 28, 2016 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)
Capital and Financing Lease Obligations Number of Leases			21		21		20
Interest Expense, Debt, Excluding Amortization			$ 600	$ 700	$ 1,200	$ 1,200
Interest Costs Capitalized			100	$ 100	100	$ 100
Letter of Credit [Member]
Letters of Credit Outstanding, Amount			1,000		1,000			$ 1,000
The New Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 50,000
Line of Credit Facility, Dividend Restrictions, Maximum Amount		$ 10,000
Line of Credit Facility, Remaining Borrowing Capacity			49,000		49,000			$ 49,000
Long-Term Debt, Total			19,700		19,700
The New Credit Facility [Member] | Maximum [Member]
Debt Instrument, Maximum Dividend Payment Permitted	$ 50,000
The New Credit Facility [Member] | Prime Rate [Member]
Debt Instrument, Basis Spread on Variable Rate		0.50%
The New Credit Facility [Member] | Eurodollar [Member]
Debt Instrument, Basis Spread on Variable Rate		1.00%
The New Credit Facility [Member] | Term Loan [Member]
Debt Instrument, Face Amount			35,000		35,000
Debt Instrument, Periodic Payment, Principal					400
The New Credit Facility [Member] | Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity			50,000		50,000
Long-term Line of Credit, Total			$ 0		$ 0		$ 0
The New Credit Facility [Member] | Standby Letters of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 5,000