Leases - Net operating lease cost (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Lease Cost
Operating lease cost	$ 63.8	$ 62.8	$ 127.2	$ 124.3
Sublease income	(4.6)	(6.7)	(9.7)	(13.0)
Total lease cost	$ 59.2	$ 56.1	$ 117.5	$ 111.3