Geographic Information (Information by Geographic Area) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) Segments	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of reportable business segments of the Company \| Segments			1
Revenues	$ 682.4	$ 656.4	$ 1,321.0	$ 1,265.9
Property and equipment (including concession assets), net	8,595.7		8,595.7		$ 8,403.8
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	351.7	344.4	686.9	665.6
Property and equipment (including concession assets), net	5,351.3		5,351.3		5,227.3
MEXICO
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	330.7	$ 312.0	634.1	$ 600.3
Property and equipment (including concession assets), net	$ 3,244.4		$ 3,244.4		$ 3,176.5

Amount after accumulated depreciation, depletion and amortization of physical assets and certain intangibles used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, track structure, land, buildings, machinery and equipment, office equipment, furniture and fixtures, computer equipment and concession assets.

No definition available.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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