Long Term Debt (Schedule of Long-Term Debt Principal versus Amortization Costs) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	$ 238,869	$ 9,521
Unamortized Debt Issuance Expense	3,676	0
Medium Term Notes Due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	230,000	0
Unamortized Debt Issuance Expense	3,676
Capital Lease Obligations Due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	8,845	9,521
Other [Member]
Debt Instrument [Line Items]
Debt Instrument Carrying Amount	$ 24	$ 0

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 9

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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

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- 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

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