Leases - Maturities of Lease Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Maturities of lease liabilities [Line Items]
Capital Leases, Future Minimum Payments Due, Next Twelve Months	$ 11.1
Capital Leases, Future Minimum Payments Due in Two Years	0.0
Capital Leases, Future Minimum Payments Due in Three Years	0.0
Capital Leases, Future Minimum Payments Due in Four Years	0.0
Capital Leases, Future Minimum Payments Due in Five Years	0.0
Finance Lease, Liability, Payments, Due after Year Five	0.0
Capital Leases, Future Minimum Payments Due	11.1
Lessee, Operating Lease, Discount Rate	(92.1)
Capital Leases, Future Minimum Payments, Interest Included in Payments	(0.1)
Lessee, leases, Liability	467.3
Lessee, leases, discount rate	92.2
Sublease Income	18.0
Operating Leases
Total discounted lease liabilities	456.3	$ 0.0
Finance Leases
Total discounted lease liabilities	11.0	11.3
Total
Total discounted lease liabilities	467.3	$ 11.3
Recourse Operating Leases [Member]
Maturities of lease liabilities [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	34.8
LesseeLeasesFutureMinimumPaymentsDueNextTwelveMonths	45.9
Operating Leases, Future Minimum Payments, Due in Two Years	67.7
LesseeLeasesFutureMinimumPaymentsDueInTwoYears	67.7
Operating Leases, Future Minimum Payments, Due in Three Years	66.1
LesseeLeasesFutureMinimumPaymentsDueInThreeYears	66.1
Operating Leases, Future Minimum Payments, Due in Four Years	57.2
LesseeLeasesFutureMinimumPaymentsDueInFourYears	57.2
Operating Leases, Future Minimum Payments, Due in Five Years	54.4
LesseeLeasesFutureMinimumPaymentsDueInFiveYears	54.4
Operating Leases, Future Minimum Payments, Due Thereafter	268.2
LesseeLeasesFutureMinimumPaymentsDueThereafter	268.2
Operating Leases, Future Minimum Payments Due	548.4
Lessee leases future minimum payments due	$ 559.5