Leases - Future Minimum Lease Payments (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Operating leases
2019 (excluding the nine months ended September 30, 2019)	$ 5.9
2020	20.6	$ 19.1
2021	15.2	13.7
2022	9.7	9.3
2023	7.6	7.3
Thereafter	16.7	18.4
Total	75.7	93.1
Less: Imputed interest	(4.6)
Total lease liabilities	71.1
Finance leases
2019 (excluding the nine months ended September 30, 2019)	0.1
2020	0.5	0.1
2021	0.4	0.1
2022	0.3
2023	0.2
Total	1.5	$ 0.2
Imputed interest	(0.1)
Total lease liabilities	$ 1.4