Disposition (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Other Revenues		$ 115.4		$ 243.1
Other Operation Expense		91.4		176.4
Maintenance Expense		7.4		15.7
Depreciation and Amortization Expense		9.0		18.1
Taxes Other Than Income Taxes		3.2		7.2
Total Expense		111.0		217.4
Other Expense		(4.7)		(9.1)
Pretax Income of Discontinued Operations		(0.3)		16.6
Income Tax Expense		(0.2)		6.1
Equity Earnings of Unconsolidated Subsidiaries		0.0		(0.1)
Total Income on Discontinued Operations as Presented on the Condensed Consolidated Statements of Income	$ (2.5)	(0.1)	$ (2.5)	10.4
Acquisitions Dispositions and Discontinued Operations Textuals [Abstract]
Income (Loss) from Discontinued Operations, Net of Tax	$ (2.5)	$ (0.1)	$ (2.5)	$ 10.4