Description of the Business (Details)	12 Months Ended
Dec. 31, 2020
PCRC [Member]
Description Of The Business [Line Items]
Equity investment ownership percentage	50.00%
TCM [Member]
Description Of The Business [Line Items]
Equity investment ownership percentage	45.00%
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]
Percentage of gross revenue payable under railroad Concession to Mexican government	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	70.00%
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	79.00%
MSLLC [Member]
Description Of The Business [Line Items]
Ownership percentage of MSLLC	70.00%

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

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Percentage of gross revenue payable under railroad Concession to Mexican government.

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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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