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New Accounting Pronouncements (Details-1) - Accounting Standards Update 2015-03 - Simplifying the Presentation of Debt Issuance Costs [Member] - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2016 | Dec. 31, 2015
Other deferred charges [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
New accounting pronouncement, effect of adoption, decrease in assets and liabilities (debt issuance costs) | $ (4.1) | $ (4.3)
Long-term debt [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
New accounting pronouncement, effect of adoption, decrease in assets and liabilities (debt issuance costs) | $ (4.1) | $ (4.3)

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