Write-downs, Reserves, and Project Opening Costs, net of Recoveries (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Write-downs and reserves, and project opening costs, net of recoveries:
Cost of Property Repairs and Maintenance	$ 3.9	$ 12.1
Gain (Loss) on Disposition of Property Plant Equipment	8.5	1.8
Project opening costs	13.2	1.7
Other	(1.6)	5.1
Total write-downs, reserves, and project opening costs, net of recoveries	$ 24.0	$ 20.7