Refers to number of barge slips during the period.

No definition available.

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- Definition

Refers to the number of maritime (seagoing) vessels.

+ References

No definition available.

+ Details

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- Definition

Number of vessels damaged in collision resulting in fuel oil discharge.

+ References

No definition available.

+ Details

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- Definition

Number of companies also named as potentially responsible parties under comprehensive environmental response compensation and liability act.

+ References

No definition available.

+ Details

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- Definition

Number of spills at the site to be declared as a Superfund site.

+ References

No definition available.

+ Details

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Namespace Prefix:	kex_
Data Type:	xbrli:integerItemType
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Period Type:	instant

- Definition

Amount awarded from other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

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

- References

No definition available.

+ Details

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- 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.

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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

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Contingencies and Commitments (Details) $ in Thousands, $ in Thousands			12 Months Ended
	Jul. 16, 2019 USD ($)	Jul. 16, 2019 CAD ($)	Dec. 31, 2019 BargeSlip Spill Company	Mar. 22, 2014 Vessel TankBarge
Loss Contingency [Abstract]
Loss contingency, settlement charges	$ 2,200	$ 2,900
Collision with M/S Summer Wind [Member]
Loss Contingency [Abstract]
Number of vessels involved in collision \| Vessel				2
Number of vessels damaged in collision resulting in fuel oil discharge \| TankBarge				1
Portland Harbor Superfund Site [Member]
Site Contingency [Line Items]
Number of other companies also named as Potentially Responsible Parties ("PRPs") \| Company			250
Number of spills \| Spill			4
SBA Shipyard Site [Member]
Site Contingency [Line Items]
Number of barge slips \| BargeSlip			3