Lease Obligations (Future Minimum Lease Commitments) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Capital Lease Obligations [Abstract]
Capital leases, future minimum payments due, next twelve months	$ 44.1
Capital leases, future minimum payments due in two years	35.6
Capital leases, future minimum payments due in three years	27.1
Capital leases, future minimum payments due in four years	19.5
Capital leases, future minimum payments due in five years	6.9
Capital leases, future minimum payments due thereafter	0.9
Capital leases, total future minimum payments	134.1
Less amounts representing interest	(8.1)
Total capital lease obligations, net of interest	126.0	79.0
Less current portion	(41.3)
Long term portion of capital lease obligations, net of interest	84.7
Operating Lease Obligations [Abstract]
Operating leases, future minimum payments due, next twelve months	54.3
Operating leases, future minimum payments, due in two years	43.8
Operating leases, future minimum payments, due in three years	25.0
Operating leases, future minimum payments, due in four years	12.0
Operating leases, future minimum payments, due in five years	5.2
Operating leases, future minimum payments, due thereafter	5.3
Operating leases, total future minimum payments	$ 145.6