Leases - Lease Cost (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Finance lease cost:
Amortization of right-of-use assets	$ 7.8
Interest on lease liabilities	2.3
Net finance lease cost	10.1
Operating lease cost	23.6
Variable lease cost	0.7
Sublease income	(0.1)
Total lease cost	$ 34.3