Description of the Business (Details)	12 Months Ended
Dec. 31, 2014
MSLLC [Member]
Description Of The Business [Line Items]
Ownership percentage of MSLLC	70.00%
PCRC [Member]
Description Of The Business [Line Items]
Equity investment ownership percentage	50.00%
Southern Capital [Member]
Description Of The Business [Line Items]
Equity investment ownership percentage	50.00%
FTVM [Member]
Description Of The Business [Line Items]
Equity investment ownership percentage	25.00%
PTC-220 [Member]
Description Of The Business [Line Items]
Equity investment ownership percentage	14.00%
KCSM [Member]
Description Of The Business [Line Items]
Initial percentage of gross revenue payable under railroad Concession to Mexican Government	0.50%
Initial period of time for payments due under railroad Concession to Mexican Government	15 years
Date the percentage of revenue payable to the Mexican government increased under the Concession	Jun. 24, 2012
Percentage of gross revenue payable under railroad Concession to Mexican Government after initial fifteen year period	1.25%
KCSM [Member] \| Maximum [Member]
Description Of The Business [Line Items]
Additional Concession renewal period	50 years
KCSR [Member] \| Unionized Employees Concentration Risk [Member] \| Number of Employees, Total [Member]
Description Of The Business [Line Items]
Percentage of employees covered by collective bargaining or labor agreements	80.00%
KCSM Servicios [Member] \| Unionized Employees Concentration Risk [Member] \| Number of Employees, Total [Member]
Description Of The Business [Line Items]
Percentage of employees covered by collective bargaining or labor agreements	80.00%

Additional period that the concession from the Mexican government may be renewed under certain conditions.

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Date percentage of revenue payable to Mexican government increases under the concession.

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Initial percentage of gross revenue payable under railroad concession to Mexican government.

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Initial period of time for payments due under railroad concession to Mexican government.

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Percentage of gross revenue payable under railroad concession to Mexican government after initial fifteen year period.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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