Leases - Operating Lease Costs, and Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Leases [Abstract]
Operating lease cost	$ 14.9	$ 12.3	$ 28.6	$ 25.2
Short-term and variable lease cost	5.3	5.6	10.5	13.1
Total lease cost	$ 20.2	$ 17.9	39.1	38.3
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash outflows - Payments on operating leases			27.9	25.2
Right-of-use assets obtained in exchange for new lease obligations:
Operating leases			$ 45.4	$ 24.6