Concession duty expense payable to the Mexican Government

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Period Type:	duration

- Definition

Initial percentage of gross revenue payable under railroad Concession to Mexican Government

+ Details

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- Definition

Initial period of time for payments due under railroad Concession to Mexican Government

+ Details

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Period Type:	duration

- Definition

Number of letters of credit issued.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Percentage of gross revenue payable under railroad Concession to Mexican Government after initial fifteen year period

+ Details

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Namespace Prefix:	ksu
Data Type:	num:percentItemType
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- Definition

Percentage guarantee by the Company of an unconsolidated affiliate's reserves or additional loans.

+ Details

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Namespace Prefix:	ksu
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: 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)(2))

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

+ Details

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Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Commitments and Contingencies (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 years	Sep. 30, 2010
Equipment Loans [Member]
Number of letters of credit issued	4		4
Letters of credit outstanding, amount	$ 1.5		$ 1.5
Percent guarantee of unconsolidated affiliate debt	50.00%		50.00%
7.0% Senior Secured Notes due November 2026 [Member] \| Panama Canal Railway Company [Member]
Interest rate, stated percentage	7.00%		7.00%
Maturity date on debt			Nov. 01, 2026
Debt Service Reserve or Liquidity Reserve [Member]
Letters of credit outstanding, amount	3.9		3.9
Percent guarantee of unconsolidated affiliate debt	50.00%		50.00%
KCSM [Member]
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 (years)			15
Percentage of gross revenue payable under railroad Concession to Mexican Government after initial fifteen year period			1.25%
Concession duty expense	$ 1.3	$ 1.0	$ 3.7	$ 3.1