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

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

+ References

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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.

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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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LONG-TERM DEBT - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Jun. 30, 2014	Apr. 30, 2012
Debt Instrument
Principal	$ 1,500,000	$ 1,500,000
Unamortized Debt Issuance Costs	14,380	16,824
Notes 5.875 Percent [Member]
Debt Instrument
Principal	750,000	750,000
Unamortized Debt Issuance Costs	$ 6,978	$ 8,343
Interest rate (as a percent)	5.875%	5.875%		5.875%
Notes 4.375 Percent [Member]
Debt Instrument
Principal	$ 750,000	$ 750,000
Unamortized Debt Issuance Costs	$ 7,402	$ 8,481
Interest rate (as a percent)	4.375%	4.375%	4.375%