Leases - Cash flow information, weighted average remaining term and discount rate (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Leases
Gains on sale and leaseback transactions, net		$ (0.2)
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$ 114.3	118.3
Right-of-use assets obtained in exchange for operating lease liabilities	$ 2.6	$ 2.3
Weighted-average remaining lease term - operating leases	25 years		25 years
Weighted-average discount rate - operating leases	6.60%		6.60%