Revenue From Contracts With Customers (Narrative) (Details)	6 Months Ended
Jun. 30, 2018 USD ($) item	Jun. 30, 2017 USD ($)
Disaggregation of Revenue [Line Items]
Contract cost \| $	$ 0
Credit balances \| $	1,583,712
Energy Sales [Member]
Disaggregation of Revenue [Line Items]
Unbilled revenue \| $	$ 7,749,823	$ 7,887,991
Energy Sales [Member] \| Minimum [Member]
Disaggregation of Revenue [Line Items]
Payment terms	15 days
Energy Sales [Member] \| Maximum [Member]
Disaggregation of Revenue [Line Items]
Payment terms	30 days
Energy Sales [Member] \| Sales Revenue [Member] \| Customer Concentration Risk [Member]
Disaggregation of Revenue [Line Items]
Customer percentage of sales revenue	94.70%	92.60%
Energy Sales [Member] \| Sales Revenue [Member] \| Credit Concentration Risk [Member]
Disaggregation of Revenue [Line Items]
Customer percentage of sales revenue	0.10%
Retail Customer [Member]
Disaggregation of Revenue [Line Items]
Number of components of monthly billing \| item	4
Wholesale Customer [Member]
Disaggregation of Revenue [Line Items]
Number of components of monthly billing \| item	4
Economy [Member]
Disaggregation of Revenue [Line Items]
Number of components of monthly billing \| item	3
Wheeling [Member] \| Sales Revenue [Member] \| Customer Concentration Risk [Member]
Disaggregation of Revenue [Line Items]
Customer percentage of sales revenue	4.10%	3.50%
Gas Sales [Member] \| Sales Revenue [Member] \| Customer Concentration Risk [Member]
Disaggregation of Revenue [Line Items]
Customer percentage of sales revenue	0.00%	2.90%
Other Miscellaneous [Member] \| Sales Revenue [Member] \| Customer Concentration Risk [Member]
Disaggregation of Revenue [Line Items]
Customer percentage of sales revenue	1.20%	1.00%

Number of components of monthly billing

No definition available.

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- Definition

Payment terms in contract with customer.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

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-Name Accounting Standards Codification
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-Publisher FASB
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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

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84173487&loc=SL51747714-108306

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130556-203045

+ Details

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Balance Type:	credit
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- Definition

Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

+ 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 210.5-02.3(c)(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=68054760&loc=d3e55302-109406

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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