Basis of Presentation (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) segment	Jun. 30, 2018 USD ($)	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of reportable segments | segment			2
Operating lease liability	$ 252.4		$ 252.4
Operating lease assets	233.1		233.1			$ 0.0
Tax Cuts and Jobs Act, reclassification from AOCI to retained earnings, tax effect			5.4
Property and equipment, net	8,093.6		8,093.6			$ 8,020.1
Depreciation, amortization and depletion	264.2	$ 255.5	515.8	$ 518.6
Cash provided by operating activities			1,135.6	$ 1,191.0
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability					$ 256.3
Operating lease assets					236.2
Adjustments for New Accounting Principle, Early Adoption ASU 2018-15
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets					28.7
Property and equipment, net					$ (28.7)
Depreciation, amortization and depletion	$ 8.2		16.3
Cash provided by operating activities			$ 10.2