Subsequent Event (Details) (Subsequent Event [Member], KCSM [Member], Senior Notes [Member], USD $) In Millions, unless otherwise specified				0 Months Ended
Jan. 22, 2010 KCSM 8.0% Senior Notes, Due February 1, 2018 [Member]	Dec. 20, 2010 6 5/8% Senior Notes, Due December 15, 2020 [Member]	May 20, 2011 6 1/8% Senior Notes, Due June 15, 2021 [Member]	Apr. 10, 2013 Debt Instruments, Cash Tender Offer [Member] Maximum [Member]
Subsequent Event [Line Items]
Debt instrument, stated interest rate	8.00%	6.625%	6.125%
Maximum aggregate consideration for early repayment of senior debt				$ 650.0

Interest rate stated in the contractual debt agreement.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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