Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Operating lease right-of-use assets	$ 94.6	$ 0.0
Current operating lease liabilities	26.0	0.0
Non-current Operating Lease Liabilities	73.1	0.0
Total operating lease liabilities	99.1
Finance leases:
Property, at cost	22.5
Less – accumulated depreciation and amortization	13.1
Net property	9.4	$ 8.7
Current obligations of finance leases	2.1
Finance leases, net of current obligations	8.7
Total finance lease liabilities	$ 10.8
Operating Lease, Weighted Average Remaining Lease Term	5 years 22 days
Finance Lease, Weighted Average Remaining Lease Term	5 years 7 months 5 days
Operating Lease, Weighted Average Discount Rate, Percent	3.60%
Finance Lease, Weighted Average Discount Rate, Percent	7.10%