Refers to lease agreements expiring terms, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

+ Details

Name:	kex_LeaseAgreementsExpiringTerms
Namespace Prefix:	kex_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of charter agreement for terms of one year or less related to towing vessels.

+ References

No definition available.

+ Details

Name:	kex_PercentageOfCharterAgreementForTermsOfOneYearOrLess
Namespace Prefix:	kex_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Leases, Schedule of Rent Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property Subject To Or Available for Operating Lease [Line Items]
Rental expense	$ 144,155	$ 162,582	$ 166,542
Other Buildings and Equipment [Member]
Property Subject To Or Available for Operating Lease [Line Items]
Rental expense	15,915	11,182	9,383
Barges [Member] \| Marine Equipment [Member]
Property Subject To Or Available for Operating Lease [Line Items]
Rental expense	$ 11,550	13,791	14,092
Towing Vessels [Member]
Property Subject To Or Available for Operating Lease [Line Items]
Percentage of charter agreement for terms of one year or less	75.00%
Towing Vessels [Member] \| Marine Equipment [Member]
Property Subject To Or Available for Operating Lease [Line Items]
Rental expense	$ 116,690	$ 137,609	$ 143,067
Minimum [Member] \| Barges [Member]
Property Subject To Or Available for Operating Lease [Line Items]
Lease agreements expiring terms	1 year
Minimum [Member] \| Towing Vessels [Member]
Property Subject To Or Available for Operating Lease [Line Items]
Lease agreements expiring terms	30 days
Maximum [Member] \| Barges [Member]
Property Subject To Or Available for Operating Lease [Line Items]
Lease agreements expiring terms	12 years
Maximum [Member] \| Towing Vessels [Member]
Property Subject To Or Available for Operating Lease [Line Items]
Lease agreements expiring terms	10 years