Leases - Future lease obligations (Details) $ in Millions	Sep. 30, 2019 USD ($)
Operating future lease obligations:
2019 (remainder of year)	$ 7.8
2020	30.1
2021	27.7
2022	23.6
2023	21.9
Thereafter	64.7
Total lease payments	175.8
Less interest	26.5
Total	149.3
Finance leases maturities:
2019 (excluding three months ended March 31, 2019)	0.3
2020	0.7
2021	0.1
2022	0.1
Total lease payments	1.2
Total	$ 1.2