Leases - Schedule of Components of Lease Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Lessor, Lease, Description [Line Items]
Operating lease cost	$ 6.3	$ 63.0	$ 67.1	$ 181.4
Short-term lease	4.7	7.5	18.9	25.4
Variable lease	5.0	14.9	14.7	43.3
Operating lease cost	16.0	85.4	100.7	250.1
Amortization of leased assets	1.3	0.9	2.8	1.7
Interest on lease liabilities	0.3	0.2	0.8	0.6
Lease impairment	0.3	0.0	94.5	0.0
Net lease cost	19.2	$ 86.5	200.1	$ 252.4
General and Administrative Expense
Lessor, Lease, Description [Line Items]
Lease impairment	$ 1.3		$ 1.3