Property and Equipment - Fully Depreciated Assets and Assets Under Capital Lease (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Fully depreciated assets	$ 318.6	$ 289.7
Capital Leases, Balance Sheet, Assets by Major Class, Net [Abstract]
Capital Leased Assets, Gross	342.9	339.9
Accumumlated Amortization	(104.6)	(83.5)
Assets Under Capital Lease Obligations, Net	238.3	256.4
Building [Member]
Capital Leases, Balance Sheet, Assets by Major Class, Net [Abstract]
Capital Leased Assets, Gross	329.6	331.0
Vehicles [Member]
Capital Leases, Balance Sheet, Assets by Major Class, Net [Abstract]
Capital Leased Assets, Gross	13.0	8.6
Equipment [Member]
Capital Leases, Balance Sheet, Assets by Major Class, Net [Abstract]
Capital Leased Assets, Gross	$ 0.3	$ 0.3