Leases Leases - Lease cost (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Lease, Cost [Abstract]
Operating lease cost(a)	$ 97.2
Short-term lease cost	27.2
Amortization of right-of-use assets	27.4
Interest on lease liabilities	7.4
Total lease cost	$ 159.2	$ 151.3