The age requirement of defined benefit plan.

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- Definition

Amount of cost (credit) included in regulatory deferral expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

+ References

No definition available.

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- Definition

Amount of expected amortization of net gain (losses) on regulatory deferral liabilities of defined benefit plan.

+ References

No definition available.

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- Definition

The minimum period of service required under defined benefit plan.

+ References

No definition available.

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- Definition

The period before benefits ae fully vested under defined benefit plan.

+ References

No definition available.

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- Definition

The percentage that the employer will match contribution of employee contribution under defined contribution plan.

+ References

No definition available.

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- Definition

Percentage employer matches of the employee's percentage contribution matched at 100% match.

+ References

No definition available.

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- Definition

Percentage employer matches 50% of the employee's percentage contribution matched.

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Represents the employer matching contribution expressed as a percent of match, second tranche.

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No definition available.

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- Definition

Minimum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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- Definition

Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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No definition available.

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Note 9 - Employee Benefit Plans (Details Textual)	12 Months Ended
Note 9 - Employee Benefit Plans (Details Textual)	Sep. 30, 2024	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)
Defined Benefit Plan, Expected Amortization, Next Fiscal Year		$ 64,000
Defined Benefit Plan, Expected Amortization Of Net Gains (Losses), Regulatory Deferral		243,000
Defined Benefit Plan, Expected Amortization of Net Gains (Losses), Regulatory Deferral Liabilities		$ 31,000
The 401K Plan [Member]
Defined Contribution Plan, Minimum Annual Contributions Per Employee, Percent		1.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent		50.00%
Defined Contribution Plan, Employer Matching Contribution, Match Percentage		100.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of 100 Percent Match		4.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Match, Second Tranche		50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of 50% Match		2.00%
Defined Benefit Plan, Equity Securities [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage			29.00%
Defined Benefit Plan, Debt Security [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage			70.00%
Defined Benefit Plan, Cash [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage			1.00%
Pension Plan [Member]
Defined Benefit Plan, Period Before Benefits are Fully Vested (Year)		5 years
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-Term Rate of Return on Plan Assets		4.50%	4.75%
Defined Benefit Plan, Plan Assets, Contributions by Employer		$ 0	$ 0
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		$ 0
Pension Plan [Member] \| Forecast [Member]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-Term Rate of Return on Plan Assets	4.50%
Pension Plan [Member] \| Fixed Income Securities [Member]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		75.00%	70.00%
Pension Plan [Member] \| Defined Benefit Plan, Equity Securities [Member]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		25.00%	30.00%
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage		27.00%	13.00%
Pension Plan [Member] \| Defined Benefit Plan, Debt Security [Member]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		75.00%
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage		72.00%	0.00%
Pension Plan [Member] \| Defined Benefit Plan, Cash [Member]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		0.00%
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage		1.00%	87.00%
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Minimum Service Requirement (Year)		10 years
Defined Benefit Plan, Age Requirement		55
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-Term Rate of Return on Plan Assets		3.95%	4.24%
Defined Benefit Plan, Plan Assets, Contributions by Employer		$ 0	$ 0
Other Postretirement Benefits Plan [Member] \| Forecast [Member]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-Term Rate of Return on Plan Assets	4.24%
Other Postretirement Benefits Plan [Member] \| Fixed Income Securities [Member]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		70.00%	50.00%
Other Postretirement Benefits Plan [Member] \| Defined Benefit Plan, Equity Securities [Member]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		30.00%	50.00%
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage		43.00%	48.00%
Other Postretirement Benefits Plan [Member] \| Defined Benefit Plan, Debt Security [Member]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		70.00%
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage		37.00%	51.00%
Other Postretirement Benefits Plan [Member] \| Defined Benefit Plan, Cash [Member]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		0.00%
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage		20.00%	1.00%