Leases Leases - Operating future minimum lease payments (Details) $ in Millions	Dec. 31, 2019 USD ($)
Operating Leased Assets [Line Items]
2020	$ 85.7
2021	67.3
2022	51.8
2023	41.4
2024	30.5
Later years	117.1
Total Lease Payments	393.8
Less: Interest	109.5
Present value of lease liabilities	284.3
Facilities
Operating Leased Assets [Line Items]
2020	57.1
2021	50.5
2022	42.9
2023	36.4
2024	29.1
Later years	117.1
Total Lease Payments	333.1
Less: Interest	104.4
Present value of lease liabilities	228.7
Vehicles
Operating Leased Assets [Line Items]
2020	7.8
2021	4.2
2022	1.4
2023	0.2
2024	0.0
Later years	0.0
Total Lease Payments	13.6
Less: Interest	0.6
Present value of lease liabilities	13.0
Other
Operating Leased Assets [Line Items]
2020	20.8
2021	12.6
2022	7.5
2023	4.8
2024	1.4
Later years	0.0
Total Lease Payments	47.1
Less: Interest	4.5
Present value of lease liabilities	$ 42.6