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Note 10 - Debt and Commitments (Details Textual)		1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
Note 10 - Debt and Commitments (Details Textual)	Jan. 01, 2023	Mar. 31, 2024 USD ($)	Nov. 30, 2015 USD ($) a ft²	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2013 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Oct. 31, 2020
Investment Margin Account				$ 25,000,000		$ 25,000,000			$ 27,500,000
Proceeds from Sale and Maturity of Debt Securities, Available-for-Sale		$ 40,579,000					$ 40,579,000
Repayments of Other Long-Term Debt						2,500,000	45,579,000
Payments to Acquire Property, Plant, and Equipment					$ 18,000		23,000
Operating Lease, Expense				91,000	71,000	157,000	141,000
The 401(k) Retirement Plan [Member]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	100.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	4.00%
Defined Contribution Plan, Cost				159,000	156,000	334,000	332,000
The 409(A) Non-qualified Deferred Compensation Plan [Member]
Deferred Compensation Arrangement with Individual, Recorded Liability		980,000		1,015,000	980,000	1,015,000	980,000		$ 509,000
Building [Member] \| UTAH
Area of Real Estate Property \| ft²			30,700
Land [Member] \| UTAH
Area of Land \| a			3.6
Payments to Acquire Property, Plant, and Equipment			$ 1,240,000
Margin Account [Member]
Proceeds from Issuance of Debt						45,500,000		$ 29,500,000
Investment Margin Account										$ 75,000,000
Debt Instrument, Face Amount		$ 27,500,000		25,000,000	$ 27,500,000	$ 25,000,000	$ 27,500,000
Repayments of Other Long-Term Debt				$ 2,500,000
Debt Instrument, Basis Spread on Variable Rate								0.50%
Debt Instrument, Interest Rate, Effective Percentage				5.00%		5.00%
Real Estate Bank Loan Secured by Logan Office [Member]
Loans Payable to Bank			$ 2,260,000	$ 1,040,000.00		$ 1,040,000.00
Long-Term Debt, Percentage Bearing Fixed Interest, Percentage Rate			4.66%								3.33%
Long-Term Debt, Term											10 years
Debt Instrument, Periodic Payment						$ 16,700