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

Unamortized Loss on Early Retirement of Debt Amortization Period

+ References

No definition available.

+ Details

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- Definition

Unamortized loss on early retirement of debt deferred as regulatory asset

+ 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

+ Details

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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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Long-Term Debt (Narrative) (Details)	1 Months Ended	12 Months Ended
Long-Term Debt (Narrative) (Details)	Dec. 31, 2019 USD ($)	Sep. 30, 2020 USD ($) debt_instrument	Sep. 30, 2019 USD ($)	Jun. 30, 2019 instrument_held	Jun. 30, 2019 debt_instrument
Debt Instrument [Line Items]
Promissory Notes term		20 years
Unamortized loss on early retirement of debt deferred as regulatory asset		$ 1,598,620	$ 1,712,808
Unamortized loss on early retirement of debt, amortization period		20
Debt covenant, maximum ratio of total long-term debt to total capitalization		65.00%
RGC Midstream, LLC
Debt Instrument [Line Items]
Number of notes		2		2	2
RGC Midstream, LLC \| Unsecured Debt
Debt Instrument [Line Items]
Debt covenant, maximum ratio of priority indebtedness to total assets		15.00%
RGC Midstream, LLC \| Unsecured Debt \| Unsecured term notes payable, at 30-day LIBOR plus 1.35% due December 29, 2022
Debt Instrument [Line Items]
Debt instrument, face amount	$ 41,000,000		$ 26,000,000
RGC Midstream, LLC \| Unsecured Debt \| Unsecured term notes payable, at 30-day LIBOR plus 1.35% due December 29, 2022 \| 30-day LIBOR
Debt Instrument [Line Items]
Variable rate basis points (as a percent)	1.35%	1.35%	1.35%
RGC Midstream, LLC \| Unsecured Debt \| Unsecured term notes payable, at 30-day LIBOR plus 1.15%, due June 12, 2026
Debt Instrument [Line Items]
Debt instrument, face amount		$ 14,000,000
Fixed rate related to interest rate swap		3.24%
RGC Midstream, LLC \| Unsecured Debt \| Unsecured term notes payable, at 30-day LIBOR plus 1.20%, due June 1, 2024
Debt Instrument [Line Items]
Debt instrument, face amount		$ 10,000,000
Fixed rate related to interest rate swap		3.14%
Roanoke Gas \| Unsecured Debt
Debt Instrument [Line Items]
Debt covenant, maximum ratio of priority indebtedness to total assets		15.00%
Roanoke Gas \| Unsecured Debt \| Unsecured term notes payable at 3.60%, due on December 6, 2029
Debt Instrument [Line Items]
Debt instrument, face amount	$ 10,000,000
Promissory Notes term	10 years
Stated rate	3.60%	3.60%
Roanoke Gas \| Unsecured Debt \| Unsecured term note payable, at 30-day LIBOR plus 0.90%, November 1, 2021
Debt Instrument [Line Items]
Debt instrument, face amount		$ 7,000,000
Fixed rate related to interest rate swap		2.30%
Roanoke Gas \| Unsecured Debt \| Unsecured term note payable, at 30-day LIBOR plus 0.90%, November 1, 2021 \| 30-day LIBOR
Debt Instrument [Line Items]
Variable rate basis points (as a percent)		0.90%	0.90%
Roanoke Gas \| Unsecured Senior Notes
Debt Instrument [Line Items]
Debt covenant, maximum ratio of priority indebtedness to total assets		15.00%