Fixed interest rate related to the interest rate derivative.

No definition available.

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- Definition

Contractual rate at which a foreign currency can be purchased or sold.

+ References

No definition available.

+ Details

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- Details

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7668309&loc=d3e80748-113994

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- Definition

Aggregate notional amount of all foreign currency derivatives not designated as hedging instruments. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

+ Details

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- Definition

Aggregate notional amount of all interest rate derivatives designated as hedging instruments in cash flow hedges. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

+ References

+ Details

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

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Derivative Instruments (Narrative) (Details) In Millions, unless otherwise specified		3 Months Ended		3 Months Ended
	Mar. 31, 2013 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] USD ($)	Mar. 31, 2013 KCSR [Member] Designated as Hedging Instrument [Member] Interest Rate Swaps [Member] USD ($)	Mar. 31, 2012 KCSR [Member] Designated as Hedging Instrument [Member] Interest Rate Swaps [Member] USD ($) Interest_Rate_Swaps	Mar. 31, 2013 KCSM [Member] Not Designated as Hedging Instrument [Member] Foreign Currency Forward Contract [Member] USD ($)	Mar. 31, 2013 KCSM [Member] Not Designated as Hedging Instrument [Member] Foreign Currency Forward Contract [Member] MXN
Derivative [Line Items]
Number of amortizing interest rate swaps entered into by the Company			4
Aggregate notional amount of amortizing interest rate swaps		$ 300.5	$ 320.0
Amortizing interest rate swaps, fixed interest rate		0.4942%
Derivative maturity date		Mar. 31, 2014		Dec. 31, 2013	Dec. 31, 2013
Aggregate notional amount of foreign currency forward contracts				250.0	3,275.3
Weighted average forward exchange rate of derivatives (in Ps per USD)					13.10
Net losses to be reclassified from accumulated other comprehensive loss into interest expense over the next 12 months	$ (0.7)