Refers to the amount paid to retire outstanding debt in relation to business acquisition.

No definition available.

Name:	kex_BusinessAcquisitionCostOfAcquiredEntityCashPaidForDebtRetirement
Namespace Prefix:	kex_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Term used to define maximum possible output of an economy.

+ References

No definition available.

+ Details

Name:	kex_CapacityInDeadweightTonsOfPurchasedProductiveAssets
Namespace Prefix:	kex_
Data Type:	num:weightItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to the fair value of contingent earnout provision payable in future.

+ References

No definition available.

+ Details

Name:	kex_FairValueOfContingentConsideration
Namespace Prefix:	kex_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Refers to the number of barge equipped with tanks that may carry any one of a great variety of liquid commodities, such as petroleum and petroleum products, chemicals, and fertilizers.

+ References

No definition available.

+ Details

Name:	kex_NumberOfDoubledHulledTankBarges
Namespace Prefix:	kex_
Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to the number of productive assets purchased in relation to acquisition.

+ References

No definition available.

+ Details

Name:	kex_NumberOfProductiveAssetsPurchased
Namespace Prefix:	kex_
Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow as a result of payment of contingent liability by the entity during the period.

+ References

No definition available.

+ Details

Name:	kex_PaymentOfContingentLiability
Namespace Prefix:	kex_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Term used to define maximum possible output of an economy.

+ References

No definition available.

+ Details

Name:	kex_ProductiveAssetsCapacity
Namespace Prefix:	kex_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cash paid to acquire the entity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph f(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-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

Name:	us-gaap_BusinessAcquisitionCostOfAcquiredEntityCashPaid
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The acquisition-date fair value of the equity interests of the acquirer, including the number of instruments or interests issued or issuable in consideration for the business combination.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 39

-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 FASB

-Name Emerging Issues Task Force (EITF)

-Number 88-16

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph f(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

Name:	us-gaap_BusinessAcquisitionCostOfAcquiredEntityEquityInterestsIssuedAndIssuable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-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

Name:	us-gaap_BusinessAcquisitionCostOfAcquiredEntityPurchasePrice
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

For an acquired entity, price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

Name:	us-gaap_BusinessAcquisitionSharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_BusinessCombinationConsiderationTransferredAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

+ References

No definition available.

+ Details

Name:	us-gaap_BusinessCombinationIntegrationRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

ACQUISITIONS (Details) (USD $)	3 Months Ended			0 Months Ended		0 Months Ended		0 Months Ended
ACQUISITIONS (Details) (USD $)	Mar. 31, 2013	Mar. 31, 2012	Dec. 28, 2012 Flag Service & Maintenance, Inc. [Member]	Dec. 14, 2012 Penn Maritime Inc. and Maritime Investments LLC [Member] MMBbls	Dec. 14, 2012 Penn Maritime Inc. and Maritime Investments LLC [Member] Tugboats [Member]	Nov. 01, 2012 Allied Transportation Company [Member] bbl	Nov. 01, 2012 Allied Transportation Company [Member] Tank Barges [Member]	Nov. 01, 2012 Allied Transportation Company [Member] Offshore Dry Bulk Barges [Member] T	Nov. 01, 2012 Allied Transportation Company [Member] Coastal Tugboats [Member]
Business acquisition, consideration transferred [Abstract]
Cash consideration paid			$ 6,864,000	$ 146,750,000		$ 107,014,000
Total value of transaction				300,538,000
Stock consideration through issuance of Company common stock				29,080,000
Issue of common stock (in shares)				500,000
Shares issued per share (in dollars per share)				$ 58.16
Number of doubled hulled tank barges				18
Capacity, in barrels, of purchased productive assets (in barrels)				1.9		680,000
Number of productive assets purchased					16		10	3	7
Cash to retire outstanding debt				124,708,000
Capacity, in deadweight tons of purchased productive assets								48,000
Acquisition and integration related costs						10,000,000
Fair value of contingent earnout provision payable in 2014						9,756,000
Payment Of Contingent Liability	$ 5,000,000	$ 0