New Accounting Pronouncements (Details-1) - Accounting Standards Update 2015-03 - Simplifying the Presentation of Debt Issuance Costs [Member] - USD ($) $ in Millions	Sep. 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)	$ 4.0	$ 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)	$ 4.0	$ 4.3