Long-Term Debt Long-Term Debt Schedule (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Secured Debt	$ 850,000	$ 415,125
Unamortized Debt Issuance Expense	(19,915)	(3,300)
Long-term Debt	830,085	411,857
$150 Million Revolving Credit Facility, Due June 2020 [Member]
Debt Instrument [Line Items]
Secured Debt	50,000	0
Term-B Loan Facility repaid June 2015 [Member]
Debt Instrument [Line Items]
Secured Debt	0	180,312
$825 Million Term B Loan Facility, due June 2022 [Member]
Debt Instrument [Line Items]
Secured Debt	800,000	0
$125 million revolving credit facility, repaid June 2015 [Member]
Debt Instrument [Line Items]
Secured Debt	0	76,000
Term-A Loan Facility repaid June 2015 [Member]
Debt Instrument [Line Items]
Secured Debt	$ 0	$ 158,813

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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-Name Accounting Standards Codification

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-SubTopic 210

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

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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.

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