Note 6 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Deferred Tax Assets, Gross, Total	$ 17,279	$ 19,154
Operating Loss Carryforwards, Expired	14,300	18,800
Operating Loss Carryforwards, Recorded in APIC	1,100
Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries	0
Undistributed Earnings of Foreign Subsidiaries	0
Income Tax Examination, Penalties and Interest Accrued, Total	0	0
Income Tax Examination, Penalties and Interest Expense, Total	0	0
Domestic Tax Authority [Member]
Operating Loss Carryforwards	50,000
Operating Loss Carryforwards, Indefinite Lived	10,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	62,000
Prepaid Expenses and Other Current Assets [Member]
Deferred Tax Assets, Gross, Total	$ 275	$ 48