Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from finance leases	$ 11.5
Operating cash flows from operating leases	296.0
Financing cash flows from finance leases	$ 4.6	$ 0.0