Significant Accounting Policies and Practices - Schedule of Impact of New Accounting Standard on the Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Assets
Prepaid expenses and other	$ 24.7	$ 17.2
Right-of-use assets	431.7	0.0
Favorable acquired lease contracts, net	0.0	17.6
Cost of contracts, net	4.3	9.2
Liabilities [Abstract]
Accrued rent	18.1	23.5
Short-term lease liabilities	115.2	0.0
Long-term lease liabilities	327.7	0.0
Unfavorable acquired lease contracts, net	0.0	24.7
Other long-term liabilities	57.1	$ 58.6
Balances without Adoption of Topic 842
Assets
Prepaid expenses and other	25.3
Right-of-use assets	0.0
Favorable acquired lease contracts, net	14.1
Cost of contracts, net	8.3
Liabilities [Abstract]
Accrued rent	26.8
Short-term lease liabilities	0.0
Long-term lease liabilities	0.0
Unfavorable acquired lease contracts, net	19.2
Other long-term liabilities	61.3
Impact of Adoption Increase/(Decrease) | Accounting Standards Update 2016-02
Assets
Prepaid expenses and other	(0.6)
Right-of-use assets	431.7
Favorable acquired lease contracts, net	(14.1)
Cost of contracts, net	(4.0)
Liabilities [Abstract]
Accrued rent	(8.7)
Short-term lease liabilities	115.2
Long-term lease liabilities	327.7
Unfavorable acquired lease contracts, net	(19.2)
Other long-term liabilities	$ (4.2)