Percentage points added to the reference rate as an additional margin.

No definition available.

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- Definition

The maximum borrowing capacity under the long-term financing agreement.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Debt Instrument, Percentage of Purchase Price Financed

+ References

No definition available.

+ Details

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Namespace Prefix:	ksu_
Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Debt instrument redemption price expressed as percent of principal amount at redemption.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Period of time until the debt instrument is scheduled to be fully repaid.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

Number of Locomotives

+ References

No definition available.

+ Details

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- Definition

The percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-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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Balance Type:	credit
Period Type:	instant

- Definition

Increase of additional borrowings on existing and new debt instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph f

-Article 4

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Interest rate stated in the contractual debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ 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)(2))

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

Reference 3: 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.

+ Details

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Decrease for amounts repaid on the credit facility for the period.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

Reference 5: 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)

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

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Long-Term Debt (Details) (KCSR [Member], USD $) In Millions, unless otherwise specified	0 Months Ended								0 Months Ended	3 Months Ended
	Jun. 01, 2012 Unsecured Debt [Member] 8% Senior Notes, Due June 1, 2015 [Member]	Feb. 24, 2012 Unsecured Debt [Member] 8% Senior Notes, Due June 1, 2015 [Member]	Jan. 25, 2012 Unsecured Debt [Member] 8% Senior Notes, Due June 1, 2015 [Member]	Jun. 01, 2012 Secured Debt [Member] Additional Term A Advances [Member]	Feb. 24, 2012 Secured Debt [Member] Additional Term A Advances [Member]	Feb. 24, 2012 Secured Debt [Member] Additional Term A Advances [Member] Federal Funds Rate Plus Percent [Member]	Feb. 24, 2012 Secured Debt [Member] Additional Term A Advances [Member] One-Month LIBOR Plus Percent [Member]	Feb. 24, 2012 Secured Debt [Member] Additional Term A Advances [Member] LIBOR Plus Percent [Member]	Feb. 21, 2012 Secured Debt [Member] RRIF Loan Agreement [Member] locomotives	Mar. 31, 2012 Revolving Credity Facility [Member] Credit Agreement [Member]
Debt Instrument [Line Items]
Outstanding aggregate principal amount of debt			$ 275.0
Debt instrument, stated interest rate			8.00%						2.96%
Debt instrument, maturity date			Jun. 01, 2015
Gross amount of debt purchased and redeemed by the Company	100.3	174.7
Redemption price expressed as percent of principal amount at redemption	104.00%
Maximum aggregate principal amount available under additional advances					275.0
Debt instrument, increase, additional borrowings				100.0	175.0
Principal amount of debt				275.0					54.6
Percentage points added to the reference rate						0.50%	1.00%	1.25%
Debt instrument, additional margin							0.25%
Debt instrument, term to maturity									25 years
Percentage of purchase price financed									80.00%
Number of locomotives									30
Credit facility, amount repaid										$ 50.0