Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: 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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- References

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- Definition

Term of the interest rate that fluctuates over time as a result of an underlying benchmark interest rate or index.

+ References

No definition available.

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- Definition

Percentage of variable interest rate paid by the counterparty on the notional amount of the interest rate derivative.

+ References

No definition available.

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- Definition

The amount of (gains) or losses on an interest rate swap deferred in the period and recorded as a regulatory asset.

+ References

No definition available.

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- Definition

The amount reclassified from regulatory assets to interest expense during the period as a result of interest rate swap settlements. The Company uses regulatory accounting treatment rather than hedge accounting to defer the unrealized gains and losses on its interest rate swap. Instead of the effective portion being recorded as other comprehensive income or loss and the ineffective portion being recognized in earnings using the cash flow hedge accounting rules provided by the derivative accounting standards, the entire unrealized swap value is recorded as a regulatory asset. Based on current ratemaking treatment, the Company expects the unrealized gains and losses to be recognized in rates as a component of interest expense as the swap settlements occur. Swap settlements are recorded in the income statement with the hedged item as interest expense.

+ References

No definition available.

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- Definition

The estimated amount as of the balance sheet date expected to be reclassified to interest expense from regulatory assets within the next twelve months as a result of interest rate swap settlements.

+ References

No definition available.

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- Definition

Net payment rate on interest rate derivative with the counterparty for the period.

+ References

No definition available.

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- Definition

The potential amount payable to the interest rate swap counter party due to certain violations of the terms and conditions of the swap agreement.

+ References

No definition available.

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Interest Rate Swap Agreement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Interest Rate Swap Agreement [Abstract]
Long-term debt	$ 94,656		$ 94,656		$ 92,833
Variable Rate Pennsylvania Economic Development Financing Authority Exempt Facilities Revenue Refunding Bonds, Series 2008A, due 2029 [Member]
Interest Rate Swap Agreement [Abstract]
Long-term debt	12,000		12,000		$ 12,000
Variable Rate Pennsylvania Economic Development Financing Authority Exempt Facilities Revenue Refunding Bonds, Series 2008A, due 2029 [Member] \| Interest Rate Swap [Member]
Interest Rate Swap Agreement [Abstract]
Notional amount of swap	$ 12,000		$ 12,000
Fixed interest rate	3.16%		3.16%
Net payment rate on swap	1.97%	2.53%	2.08%	2.59%
Interest rate swap settlements reclassified from regulatory assets to interest expense	$ 60	$ 76	$ 125	$ 155
Interest rate swap (gain) loss capitalized	(90)	$ 120	(347)	$ 129
Interest rate swap settlements to be reclassified during the next 12 months	207		207
Potential payment to counterparty	$ 1,762		$ 1,762
Variable Rate Pennsylvania Economic Development Financing Authority Exempt Facilities Revenue Refunding Bonds, Series 2008A, due 2029 [Member] \| LIBOR [Member] \| Interest Rate Swap [Member]
Interest Rate Swap Agreement [Abstract]
Percentage of variable interest rate	59.00%		59.00%
Term of variable rate			1 month