Intangible Assets and Goodwill (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Amortizable intangible assets
Carrying Amount	$ 194.9	$ 194.9
Accumulated Amortization	65.1	57.5
Customer relationships
Amortizable intangible assets
Carrying Amount	168.3	168.3
Accumulated Amortization	53.1	47.0
Other
Amortizable intangible assets
Carrying Amount	26.6	26.6
Accumulated Amortization	$ 12.0	$ 10.5