Long-Term Debt Schedule of Long-Term Debt (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Long-term debt obligations	$ 1,844.0us-gaap_LongTermDebt
Total	1,865.8	2,188.9
Less: Debt due within one year	24.8	332.0
Long-term debt	1,841.0	1,856.9
KCSR [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt obligations	0	0
KCSR [Member] \| Loans Payable [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt obligations	0	245.3
KCSR [Member] \| Senior Notes [Member] \| 4.30% Senior Notes, Due 2043 [Member]
Debt Instrument [Line Items]
Long-term debt obligations	446.0	445.9
KCSR [Member] \| Senior Notes [Member] \| 3.85% Senior Notes, Due 2023 [Member]
Debt Instrument [Line Items]
Long-term debt obligations	199.8	199.7
KCSR [Member] \| Secured Debt [Member] \| RRIF Loan Agreement [Member]
Debt Instrument [Line Items]
Long-term debt obligations	50.4	52.0
KCSR [Member] \| Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Capital lease obligations	8.2	9.8
KCSR [Member] \| Other Debt Obligations [Member]
Debt Instrument [Line Items]
Long-term debt obligations	0.2	0.4
Tex-Mex [Member] \| Secured Debt [Member] \| RRIF Loan Agreement [Member]
Debt Instrument [Line Items]
Long-term debt obligations	37.8	39.4
KCSM [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt obligations	0	0
KCSM [Member] \| Senior Notes [Member] \| 8.0% Senior Notes, Due 2018 [Member]
Debt Instrument [Line Items]
Long-term debt obligations	0	62.3
KCSM [Member] \| Senior Notes [Member] \| 2.35% Senior Notes, Due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt obligations	274.7	274.7
KCSM [Member] \| Senior Notes [Member] \| 3.0% Senior Notes, Due 2023 [Member]
Debt Instrument [Line Items]
Long-term debt obligations	448.4	448.2
KCSM [Member] \| Senior Notes [Member] \| Floating Rate Senior Notes, Due 2016 [Member]
Debt Instrument [Line Items]
Long-term debt obligations	250.0	250.0
Variable interest rate	0.9331%
KCSM [Member] \| Secured Debt [Member] \| 5.737% Financing Agreement, Due 2023 [Member]
Debt Instrument [Line Items]
Long-term debt obligations	39.2	43.8
KCSM [Member] \| Secured Debt [Member] \| 6.195% Financing Agreement, Due 2023 [Member]
Debt Instrument [Line Items]
Long-term debt obligations	30.4	33.9
KCSM [Member] \| Secured Debt [Member] \| 9.310% Loan Agreements, Due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt obligations	66.9	74.6
KCSM [Member] \| Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Capital lease obligations	13.6	7.4
KCSM [Member] \| Other Debt Obligations [Member]
Debt Instrument [Line Items]
Long-term debt obligations	0	1.3
KCS [Member]
Debt Instrument [Line Items]
Long-term debt	0.2	0.2
KCS [Member] \| Other Debt Obligations [Member]
Debt Instrument [Line Items]
Long-term debt obligations	$ 0.2	$ 0.2

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Amount of long-term debt and capital lease obligations including current maturities.

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Weighted average interest rate of long-term debt outstanding.

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