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

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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/presentationRef
-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 2: http://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

Reference 2: 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

Name:	us-gaap_LongTermDebtCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

Name:	us-gaap_LongTermDebtNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

+ Details

Name:	us-gaap_UnamortizedDebtIssuanceExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Debt (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
Debt (Details) - USD ($) $ in Thousands	Aug. 03, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Debt [Abstract]
Total long-term debt		$ 87,520		$ 87,520	$ 87,542
Less discount on issuance of long-term debt		(231)		(231)	(237)
Less unamortized debt issuance costs		(2,676)		(2,676)	(2,743)
Less current maturities		(44)		(44)	(44)
Long-term portion		84,569		84,569	84,518
10.17% Senior Notes, Series A, due 2019 [Member]
Debt [Abstract]
Total long-term debt		$ 6,000		$ 6,000	6,000
Interest rate		10.17%		10.17%
9.60% Senior Notes, Series B, due 2019 [Member]
Debt [Abstract]
Total long-term debt		$ 5,000		$ 5,000	5,000
Interest rate		9.60%		9.60%
1.00% Pennvest Note, due 2019 [Member]
Debt [Abstract]
Total long-term debt		$ 140		$ 140	162
Interest rate		1.00%		1.00%
10.05% Senior Notes, Series C, due 2020 [Member]
Debt [Abstract]
Total long-term debt		$ 6,500		$ 6,500	6,500
Interest rate		10.05%		10.05%
8.43% Senior Notes, Series D, due 2022 [Member]
Debt [Abstract]
Total long-term debt		$ 7,500		$ 7,500	7,500
Interest rate		8.43%		8.43%
Variable Rate Pennsylvania Economic Development Financing Authority Exempt Facilities Revenue Refunding Bonds, Series 2008A, due 2029 [Member]
Debt [Abstract]
Total long-term debt		$ 12,000		$ 12,000	12,000
4.75% York County Industrial Development Authority Revenue Bonds, series 2006, due 2036 [Member]
Debt [Abstract]
Total long-term debt		$ 10,500		$ 10,500	10,500
Interest rate		4.75%		4.75%
4.50% Pennsylvania Economic Development Financing Authority Exempt Facilities Revenue Refunding Bonds, Series 2014, due 2038 [Member]
Debt [Abstract]
Total long-term debt		$ 14,880		$ 14,880	14,880
Interest rate		4.50%		4.50%
5.00% Monthly Senior Notes, Series 2010A, due 2040 [Member]
Debt [Abstract]
Total long-term debt		$ 15,000		$ 15,000	15,000
Interest rate		5.00%		5.00%
4.00% - 4.50% York County Industrial Development Authority Exempt Facilities Revenue Bonds, Series 2015, due 2029 - 2045 [Member]
Debt [Abstract]
Total long-term debt		$ 10,000		$ 10,000	$ 10,000
4.00% - 4.50% York County Industrial Development Authority Exempt Facilities Revenue Bonds, Series 2015, due 2029 - 2045 [Member] \| Maximum [Member]
Debt [Abstract]
Interest rate		4.50%		4.50%
4.00% - 4.50% York County Industrial Development Authority Exempt Facilities Revenue Bonds, Series 2015, due 2029 - 2045 [Member] \| Minimum [Member]
Debt [Abstract]
Interest rate		4.00%		4.00%
First Line of Credit [Member]
Debt [Abstract]
Renewed line of credit		$ 13,000		$ 13,000
Maturity date				May 31, 2018
Second Line of Credit [Member]
Debt [Abstract]
Renewed line of credit		11,000		$ 11,000
Maturity date				May 31, 2018
Third Line of Credit [Member]
Debt [Abstract]
Renewed line of credit		$ 7,500	$ 5,000	$ 7,500
Maturity date				Jun. 30, 2017
Basis for interest rate		1.25%	1.50%
Fourth Line of Credit [Member] \| Subsequent Event [Member]
Debt [Abstract]
Renewed line of credit	$ 10,000
Maturity date	Jul. 31, 2017
Basis for interest rate	1.20%