Note 11 - Other Stock Plans (Details Textual) - USD ($)	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Maximum Amount Allowed For Dividend Reinvestment and Stock Purchase Plan	$ 100,000
Stock Issued During Period, Shares, Dividend Reinvestment Plan (in shares)	32,805	34,290
Stock Available for Issuance under Dividend Reinvestment Plan (in shares)	265,624
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	22,000
Restricted Stock [Member] \| Restricted Stock Plan for Outside Directors [Member]
Share Based Compensation by Share Based Payment Award, Maximum Allowed Percentage of Retainer Fee Paid Monthly in Common Stock	100.00%
Share Based Compensation by Share Based Payment Award, Percentage of Retainer Fee Paid Monthly in Common Stock	40.00%
Share Based Compensation by Share Based Payment Award, Minimum Shares Owned Requirement (in shares)	10,000
Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture	$ 299,200	$ 291,767
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares)	0	0
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)	200,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	196,559
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 21.25	$ 21.55
Restricted Stock [Member] \| RGC Resources Inc. Restricted Stock Plan [Member]
Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture	$ 169,879	$ 534,710
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	366,745
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 0	$ 23.19
Restricted Stock [Member] \| Stock Bonus Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	4,680
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period (in shares)	105	0
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 23.76

The maximum amount allowed for dividend reinvestment and stock purchase plan.

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The maximum allowed percentage of retainer fee paid monthly in common stock under share based payment arrangement.

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The minimum number of shares required to be owned under share based payment arrangement.

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Number of shares available for issuance under dividend reinvestment plan.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Number of additional shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares issued under share-based payment arrangement.

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Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

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Value, after forfeiture, of shares issued under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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