Leases - Components of lease cost (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Finance lease costs:
Amortization of right-of-use asset	$ 7.6
Interest on lease liabilities	7.8
Operating lease costs	64.8
Short-term lease costs	12.9
Variable lease costs	4.4
Total lease costs, net	$ 97.5