Leases - Additional Lease Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Operating lease cost	$ 452.9	$ 552.7	$ 464.6
Short-term lease cost	39.7
Variable lease cost	73.6	$ 68.2	$ 63.3
Operating cash outflows from operating leases	430.9
Leased assets obtained in exchange for new operating lease liabilities	$ 346.4
Weighted average remaining lease term for operating leases	6 years
Weighted average discount rate for operating leases	3.90%