Debt Instrument, Debt Covenant, Ratio of Long-term Debt to Total Capitalization, Maximum

No definition available.

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- Definition

Debt Instrument, Debt Covenant, Ratio of Priority Debt to Total Assets, Maximum

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Number of Instruments

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Long-Term Debt (Narrative) (Details)				9 Months Ended
Long-Term Debt (Narrative) (Details)	Mar. 26, 2020 USD ($)	Dec. 23, 2019 USD ($)	Dec. 06, 2019 USD ($)	Jun. 30, 2020 USD ($) debt_instrument	Sep. 30, 2019 USD ($)	Jun. 13, 2019 USD ($)	Jun. 12, 2019 USD ($) instrument_held
Debt Instrument [Line Items]
Maximum percentage of Consolidated Long Term Indebtedness to Consolidated Total Capitalization				65.00%
Roanoke Gas [Member] \| Unsecured Term Notes Payable, at 3.60%, due December 6, 2029 [Member] \| Unsecured Term Notes [Member]
Debt Instrument [Line Items]
Debt term			10 years
Debt instrument, borrowing amount			$ 10,000,000
Stated percentage rate			3.60%	3.60%
Maximum percentage of Priority Indebtedness to Consolidated Total Assets				15.00%
Roanoke Gas [Member] \| Unsecured Term Notes Payable, at 4.41%, due March 28, 2031 [Member] \| Unsecured Term Notes [Member]
Debt Instrument [Line Items]
Stated percentage rate				4.41%
Roanoke Gas [Member] \| Line of Credit, at 30-day LIBOR plus 1.00%, due March 31, 2022 [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Debt term	2 years
Availability fee (as a percent)	0.15%
Roanoke Gas [Member] \| Line of Credit, at 30-day LIBOR plus 1.00%, due March 31, 2022 [Member] \| Line of Credit [Member] \| 30-day LIBOR [Member]
Debt Instrument [Line Items]
Variable rate basis points (as a percent)	1.00%			1.00%
Roanoke Gas [Member] \| Line of Credit, at 30-day LIBOR plus 1.00%, due March 31, 2022 [Member] \| Line of Credit [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity	$ 28,000,000
Roanoke Gas [Member] \| Line of Credit, at 30-day LIBOR plus 1.00%, due March 31, 2022 [Member] \| Line of Credit [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity	$ 3,000,000
Roanoke Gas [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 0.90%, due November 1, 2021 [Member] \| Unsecured Term Notes [Member]
Debt Instrument [Line Items]
Debt instrument, borrowing amount				$ 7,000,000
Effective interest rate				2.30%
Maximum percentage of Priority Indebtedness to Consolidated Total Assets				15.00%
Roanoke Gas [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 0.90%, due November 1, 2021 [Member] \| Unsecured Term Notes [Member] \| 30-day LIBOR [Member]
Debt Instrument [Line Items]
Variable rate basis points (as a percent)				0.90%
Roanoke Gas [Member] \| Unsecured Term Notes Payable, at 3.58%, due October 2, 2027 [Member] \| Unsecured Term Notes [Member]
Debt Instrument [Line Items]
Stated percentage rate				3.58%
RGC Midstream LLC [Member]
Debt Instrument [Line Items]
Debt instrument, number of instruments				2			2
RGC Midstream LLC [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 1.35%, due December 29, 2022 [Member] \| Unsecured Term Notes [Member]
Debt Instrument [Line Items]
Debt instrument, borrowing amount		$ 41,000,000			$ 26,000,000
Maximum percentage of Priority Indebtedness to Consolidated Total Assets				15.00%
RGC Midstream LLC [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 1.35%, due December 29, 2022 [Member] \| Unsecured Term Notes [Member] \| 30-day LIBOR [Member]
Debt Instrument [Line Items]
Variable rate basis points (as a percent)		1.35%		1.35%
RGC Midstream LLC [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 1.15%, due June 12, 2026 [Member] \| Unsecured Term Notes [Member]
Debt Instrument [Line Items]
Debt instrument, borrowing amount				$ 14,000,000			$ 14,000,000
Effective interest rate				3.24%			3.24%
Maximum percentage of Priority Indebtedness to Consolidated Total Assets				15.00%
RGC Midstream LLC [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 1.15%, due June 12, 2026 [Member] \| Unsecured Term Notes [Member] \| 30-day LIBOR [Member]
Debt Instrument [Line Items]
Variable rate basis points (as a percent)				1.15%
RGC Midstream LLC [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 1.20%, due June 1, 2024 [Member] \| Unsecured Term Notes [Member]
Debt Instrument [Line Items]
Debt instrument, borrowing amount				$ 10,000,000		$ 10,000,000
Effective interest rate				3.14%		3.14%
Maximum percentage of Priority Indebtedness to Consolidated Total Assets				15.00%
RGC Midstream LLC [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 1.20%, due June 1, 2024 [Member] \| Unsecured Term Notes [Member] \| 30-day LIBOR [Member]
Debt Instrument [Line Items]
Variable rate basis points (as a percent)				1.20%