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

Amount of investment required by credit agreement to be made independently by the Company to the related equity investment after an agreed upon amount has been borrowed on the note.

+ References

No definition available.

+ Details

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- Definition

The maximum amount that can be borrowed on note payable before the Company must independently make an agreed upon capital contribution to related equity investment.

+ 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ 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

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ 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://www.xbrl.org/2003/role/presentationRef
-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)			1 Months Ended		6 Months Ended	9 Months Ended
Long-Term Debt (Narrative) (Details)	Mar. 27, 2017 USD ($)	Nov. 01, 2016 USD ($)	Dec. 31, 2015 USD ($) instruments_held	Oct. 31, 2015 debt_instrument	Mar. 31, 2017	Jun. 30, 2017
Debt Instrument [Line Items]
Maximum percentage of Consolidated Long Term Indebtedness to Consolidated Total Capitalization						65.00%
Maximum percentage of Priority Indebtedness to Consolidated Total Assets						15.00%
Unsecured Term Notes [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 0.90%, due November 1, 2021 [Member]
Debt Instrument [Line Items]
Debt instrument, borrowing amount		$ 7,000,000
Effective interest rate		2.30%
Roanoke Gas [Member]
Debt Instrument [Line Items]
Debt term					1 year
Roanoke Gas [Member] \| Line of Credit [Member] \| Line of Credit, at 30-day LIBOR plus 1.00%, due March 31, 2019 [Member]
Debt Instrument [Line Items]
Debt term	2 years
Availability fee (as a percent)	0.15%
Roanoke Gas [Member] \| Line of Credit [Member] \| Line of Credit, at 30-day LIBOR plus 1.00%, due March 31, 2019 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Line of credit, maximum borrowing limit	$ 10,000,000
Roanoke Gas [Member] \| Line of Credit [Member] \| Line of Credit, at 30-day LIBOR plus 1.00%, due March 31, 2019 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Line of credit, maximum borrowing limit	$ 30,000,000
Roanoke Gas [Member] \| Line of Credit [Member] \| Line of Credit, at 30-day LIBOR plus 1.00%, due March 31, 2019 [Member] \| 30-day LIBOR [Member]
Debt Instrument [Line Items]
Variable rate basis points (as a percent)	1.00%					1.00%
Roanoke Gas [Member] \| Unsecured Term Notes [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 0.90%, due November 1, 2021 [Member]
Debt Instrument [Line Items]
Debt term		5 years
Debt instrument, borrowing amount		$ 7,000,000
Effective interest rate		2.30%
Roanoke Gas [Member] \| Unsecured Term Notes [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 0.90%, due November 1, 2021 [Member] \| 30-day LIBOR [Member]
Debt Instrument [Line Items]
Variable rate basis points (as a percent)		0.90%				0.90%
Midstream [Member]
Debt Instrument [Line Items]
Debt term				5 years
Number of unsecured Promissory Notes funding the investment \| debt_instrument				2
Equity interest percentage			1.00%	1.00%
Midstream [Member] \| Unsecured Term Notes [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 1.60%, due December 29, 2020 [Member]
Debt Instrument [Line Items]
Debt term			5 years
Number of unsecured Promissory Notes funding the investment \| instruments_held			2
Maximum borrowings			$ 17,500,000
Required amount to be provided towards capital contributions to the LLC			5,000,000
Midstream [Member] \| Unsecured Term Notes [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 1.60%, due December 29, 2020 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, borrowing amount			$ 25,000,000
Midstream [Member] \| Unsecured Term Notes [Member] \| Unsecured Term Notes Payable, at 30-day LIBOR plus 1.60%, due December 29, 2020 [Member] \| 30-day LIBOR [Member]
Debt Instrument [Line Items]
Variable rate basis points (as a percent)			1.60%			1.60%