Costs and expenses:
Costs and Expenses [Abstract]
Impairment, Long-Lived Asset, Held-for-Use, Total
Impairment of property and equipment
Details of "Other" total assets [Abstract]
Vesting period
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period
Adoption of ASU 2018-02 - reclassification to retained earnings, Income Tax (Provision) Benefit
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect
Operating Loss Carryforwards, Total
Operating loss carryforwards
Operating Loss Carryforwards
Forecast [Member]
Forecast [Member]
Lease, Cost [Abstract]
Reportable Segments [Member]
Operating Segments [Member]
Revenue Recognition [Abstract]
Other segment disclosure [Abstract]
Other segment disclosures [Abstract]
Auditor Location
Total other comprehensive income (loss), net of taxes
Other Comprehensive Income (Loss), Net of Tax
Funded status at end of year [Abstract]
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Treasury Stock [Member]
Treasury Stock [Member]
Finite-Lived Intangible Assets by Major Class [Axis]
Operating income (loss)
Operating Income (Loss)
Fair values of assets acquired and liabilities assumed, net [Abstract]
Inventory, Finished Goods, Gross, Total
Finished goods
Year two
Defined Benefit Plan, Expected Future Benefit Payment, Year Two
Concentration Risk Type [Domain]
3.46 Series A Notes Due January 19, 2023 [Member]
Three point Four Six Series A Notes Due January Nineteen Two Thousand Thirty Three [Member]
Three point four six series a notes due january nineteen two thousand thirty three.
Entity Emerging Growth Company
Represents the period in which recertification of ocean going vessels occur twice.
Period in which recertification of ocean going vessels occur twice
Period in which recertification of ocean going vessels occur twice
Refers to the number of maritime (seagoing) vessels.
Number of Maritime Vessels
Number of vessels involved in collision
Taxes on Income [Abstract]
Retirement Plans [Abstract]
Defined Benefit Plan, Additional Information [Abstract]
Refers to a diesel-powered or steam-powered boat used especially on inland waterways to push groups of barges lashed to it in front or on one side or both.
Inland Towboats [Member]
Inland Towboats [Member]
Towboat [Member]
Outstanding and Exercisable Stock Options
Share-based Payment Arrangement, Option, Exercise Price Range [Table Text Block]
Forfeited (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value
Marine transportation - A component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.
Marine Transportation [Member]
Marine Transportation [Member]
Number of reportable segments
Number of Reportable Segments
Shares available for future grants (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant
Income Tax Description [Abstract]
Income Taxes [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)
Range of Exercise Prices, lower limit (in dollars per share)
Other Comprehensive Income (Loss) [Abstract]
Geographical [Axis]
Common stock, $0.10 par value per share. Authorized 120,000,000 shares, issued 65,472,000
Common Stock, Value, Issued, Ending Balance
Common Stock, Value, Issued, Beginning Balance
Common Stock, Value, Issued, Total
Common stock, $0.10 par value per share. Authorized 120,000,000 shares, issued 65,472,000 in 2020 and 2019
Entity Address, State or Province
Discount rate
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate
Actuarial (gain) loss
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)
Share-based Payment Arrangement, Option, Exercise Price Range, Shares Outstanding, Ending Balance
Share-based Payment Arrangement, Option, Exercise Price Range, Shares Outstanding, Beginning Balance
Number Outstanding (in shares)
Revenues by Major Source
Earnings (Loss) Before Taxes
Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]
Average risk-free interest rate
Compensation Cost Breakdown in Statement of Earnings
Schedule of Costs of Retirement Plans [Table Text Block]
2023
Amount of amortization expense for assets and liabilities, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
Finite-Lived Intangible Assets and Liabilities, Amortization Expense, Year Two
Goodwill, Total
Goodwill
Balance
Balance
Goodwill
Impairments and Other Charges [Abstract]
Distributorships [Member]
Distribution Rights [Member]
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures, Total
Issuance of stock for equity awards, net of forfeitures
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures
Payments related to tax withholding for share-based compensation
Payment, Tax Withholding, Share-based Payment Arrangement
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.
Income Tax Disclosure [Line Items]
Sublease income
Sublease Income
Refers to barrel tank barges equipped with tanks that may carry any one of a great variety of liquid commodities, such as petroleum and petroleum products, chemicals, and fertilizers.
Barrel Tank Barges [Member]
Inland Barrel Tank Barges [Member]
Shares Outstanding [Abstract]
Shares outstanding [Abstract]
Issued guaranties
Guarantor Obligations, Maximum Exposure, Undiscounted
Net periodic benefit cost
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)
Acquisitions [Abstract]
Outstanding Non-Qualified or Nonincentive Stock Awards [Roll Forward]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Ultimate Health Care Cost Trend Rate
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Ultimate Health Care Cost Trend Rate
Ultimate rate
Refers to the defined contribution plan contribution as a percentage of the aggregate accumulated benefit obligation during the period.
Defined Contribution Plan Contribution Percentage, aggregate accumulated benefit obligation
Contribution percentage to defined contribution plan
Business Acquisition [Line Items]
Amount of income tax expense (benefit) from effect of Coronavirus Aid, Relief, and Economic Security (CARES) Act.
Coronavirus Aid Relief And Economic Security Act Income Tax Expense Benefit
Tax benefit related to CARES Act
Property
Deferred Tax Liabilities, Property, Plant and Equipment
Deferred revenues
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue
Represents to director plan of the equity-based compensation arrangement plan.
Director Plan [Member]
Director Plan [Member]
Net assets acquired
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net
Available borrowing capacity
Line of Credit Facility, Remaining Borrowing Capacity
Actuarial losses, Net Amount
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax
Income tax receivable
Trade - less allowance for doubtful accounts of $8,177 ($8,807 in 2020)
Accounts Receivable, after Allowance for Credit Loss, Current, Total
Trade - less allowance for doubtful accounts of $8,807 ($8,372 in 2019)
Short-term Debt, Total
Short-term debt
Refers to inland pressure tank barges equipped with tanks that may carry any one of a great variety of liquid commodities, such as petroleum and petroleum products, chemicals, and fertilizers.
Inland Pressure Tank Barges [Member]
Inland Pressure Barges [Member]
Borrowings (payments) on bank credit facilities, net
Borrowings (payments) on bank credit facilities, net
Borrowings (Payments) on bank credit facilities
Net actuarial (gain) loss
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax
Revenue recognized
Schedule of Related Party Transactions, by Related Party [Table]
City Area Code
Amount before amortization of liabilities, excluding financial liabilities and goodwill, lacking physical substance with a finite life.
Finite-Lived Intangible Liabilities, Gross
Other intangible liabilities - gross
Undistributed Earnings (Loss) Allocated to Participating Securities, Basic, Total
Undistributed earnings allocated to restricted shares
Undistributed Earnings (Loss) Allocated to Participating Securities, Basic
Other
Other Receivables
Stock Option Valuation Assumptions
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
Borrowings and Payments Under the Bank Credit Facilities
Schedule of Line of Credit Facilities [Table Text Block]
Deferred tax assets, gross
Deferred Tax Assets, Gross
Refers to the entity that is being acquired or purchased in a merger or acquisition.
Convoy Servicing Company and Agility Fleet Services, LLC [Member]
Convoy [Member]
Deferred tax assets, net of valuation allowance
Deferred Tax Assets, Net of Valuation Allowance
Retirement benefits
Pension benefits
Years to ultimate
Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate
Refers to the aggregate carrying capacity of a quantity of tank barges as measured in number of barrels.
Tank Barge Aggregate Barrel Capacity
Aggregate tank barge barrel capacity (in barrels)
Revenues:
Deferred Income Tax Liabilities, Net, Total
Deferred income taxes
Deferred Income Tax Liabilities, Net
Forfeited or expired (in dollars per share)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price
Total long-term liabilities
Liabilities, Noncurrent
Goodwill [Abstract]
Proceeds from legal settlements
Proceeds from Legal Settlements
Contingencies and commitments
Commitments and Contingencies
Amounts recognized in the consolidated balance sheets [Abstract]
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Weighted average amortization period of intangibles
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life
Accumulated benefit obligation at end of year
Defined Benefit Plan, Accumulated Benefit Obligation
2024
Amount of amortization expense for assets and liabilities, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
Finite-Lived Intangible Assets and Liabilities, Amortization Expense, Year Three
Finite-Lived Intangible Assets, Net, Ending Balance
Finite-Lived Intangible Assets, Net, Beginning Balance
Other intangible assets - net
Other intangibles, net
Finite-Lived Intangible Assets, Net
Total U.S. Federal
Federal Income Tax Expense (Benefit), Continuing Operations
Weighted Average Exercise Price, Options Exercisable (in dollars per share)
Refers to the entity that is being acquired or purchased in a merger or acquisition.
Higman Marine, Inc [Member]
Higman [Member]
Variable interest rates
Basis spread on variable rate
Scenario [Axis]
Pension Plan [Member]
Pension Benefits [Member]
Acquisitions
Business Combination Disclosure [Text Block]
Year ultimate health care cost trend rate is expected to be reached, in CCYY format.
Defined Benefit Plan, Year Health Care Cost Trend Rate, Ultimate Trend Rate
Years to ultimate
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Total
Cash and cash equivalents, beginning of year
Cash and cash equivalents, end of year
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents
Related Party [Domain]
2022
Amount of amortization expense for assets and liabilities, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
Finite-Lived Intangible Assets and Liabilities, Amortization Expense, Next Twelve Months
Other Noncash Income (Expense), Total
Other
Other Noncash Income (Expense)
CONSOLIDATED STATEMENTS OF EARNINGS [Abstract]
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]
Weighted Average Grant Date Fair Value Per Share [Abstract]
Year one
Defined Benefit Plan, Expected Future Benefit Payment, Year One
Weighted average assumptions used to determine net periodic benefit cost [Abstract]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Net cash used in investing activities
Net Cash Provided by (Used in) Investing Activities
The service period of eligible participants of the employee pension plan who have reached the age of fifty that will be grandfathered and not be impacted by the amendment to the pension plan.
Employee Pension Plan, Grandfathered Participants, Participant Service Period Who is Fifty Years Old
Service period of participants who are age fifty not impacted by pension plan amendment
Quarterly Results (Unaudited)
Quarterly Financial Information [Text Block]
Guarantor Obligations, Nature [Axis]
Employee-related Liabilities, Current, Total
Employee compensation
Employee-related Liabilities, Current
Payments to Acquire Productive Assets, Total
Capital expenditures
Capital expenditures
Purchase price
Payments to Acquire Productive Assets
Property, Plant and Equipment, Net, Ending Balance
Property, Plant and Equipment, Net, Beginning Balance
Property and equipment - net
Property, Plant and Equipment, Net
Deferred revenues
Deferred revenues
ASU 2018-02 [Member]
Accounting Standards Update 2018-02 [Member]
Common Stock, Shares, Issued, Total
Common stock, shares issued (in shares)
Accounts receivable:
Accounts Receivable, after Allowance for Credit Loss, Current [Abstract]
Higman pension plan for 2016 and 2017 year
Plan 2016 and 2017 [Member]
Plan 2016 and 2017 [Member]
Forfeited (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period
Proceeds from (Repayments of) Notes Payable, Total
Borrowings on long-term debt
Proceeds from (Repayments of) Notes Payable
Relationship term maintained by entity with customers.
Services Segments Relationship Years
Services segment's relationship term
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Equity Securities [Member]
Defined Benefit Plan, Equity Securities [Member]
Deferred Tax Liabilities, Gross, Total
Deferred tax liabilities
Deferred Tax Liabilities, Gross
Settlements
Defined Benefit Plan, Plan Assets, Payment for Settlement
Operating lease right-of-use assets
Operating lease right-of-use assets
Net earnings attributable to noncontrolling interests
Less: Net earnings attributable to noncontrolling interests
Net Income (Loss) Attributable to Noncontrolling Interest, Total
Net Income (Loss) Attributable to Noncontrolling Interest
Taxes - other than on income
Accrual for Taxes Other than Income Taxes, Current
Customers [Member]
Customer Concentration Risk [Member]
Security Exchange Name
Tabular disclosure of assets and liabilities, excluding financial assets, liabilities and goodwill, lacking physical substance with a finite life, by either major class or business segment.
Finite-lived Intangible Assets and Liabilities [Table Text Block]
Other Intangible Assets and Other Intangible Liabilities
Statistical Measurement [Domain]
Next five years
Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years
2024
Income (loss) available to Kirby common stockholders - basic
Income (loss) available to Kirby common stockholders - basic
Net Income (Loss) Available to Common Stockholders, Basic
Cash
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents
Represents to employee plan of the equity-based compensation arrangement plan.
Employee Plan [Member]
Employee Stock Award Plan [Member]
Other long-term liabilities
Other Liabilities, Noncurrent, Total
Other long-term liabilities
Finite-Lived Intangible Assets, Gross, Total
Other intangible assets - gross
Subsequent Event Type [Domain]
Maximum borrowing capacity
Line of Credit Facility, Maximum Borrowing Capacity
Long-Term Debt [Abstract]
Decrease in deferred tax asset
Increase (Decrease) in Deferred Income Taxes
Document Period End Date
Work in process
Investments [Domain]
Revolving Credit Facility [Member]
Amounts Recognized in the Consolidated Balance Sheets
Schedule of Amounts Recognized in Balance Sheet [Table Text Block]
Related party expenses
Related Party Transaction, Expenses from Transactions with Related Party
Refers to the entity that is being acquired or purchased in a merger or acquisition.
Targa Resources Corporation [Member]
Targa [Member]
Alternate Base Rate [Member]
Base Rate [Member]
Total costs and expenses
Costs and Expenses
Income (loss) available to Kirby common stockholders - diluted
Net Income (Loss) Available to Common Stockholders, Diluted
Year three
Defined Benefit Plan, Expected Future Benefit Payment, Year Three
Loss Contingencies [Table]
Tax refund amount
Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority
Common stock, shares authorized (in shares)
Year four
Defined Benefit Plan, Expected Future Benefit Payment, Year Four
Current portion of operating lease liabilities
Current portion of operating lease liabilities
Related Party [Axis]
Contract with Customer, Asset, after Allowance for Credit Loss, Total
Contract assets
Asset Allocation Among Asset Categories [Abstract]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Supplemental disclosures of cash flow information:
Supplemental Cash Flow Information [Abstract]
Adjustments to reconcile net earnings (loss) to net cash provided by operations:
Adjustments to reconcile net earnings (loss) to net cash provided by operations:
Equipment listing the barges and vessels available from Enterprise Products marine transportation.
Marine Transportation Equipment
Marine transportation equipment
Amortization of net actuarial loss, Net Amount
Amount, after tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) and settlement of defined benefit plan.
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Settlement, Reclassification Adjustment from AOCI, after Tax
Total assets
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets
Amortization of net actuarial loss, Gross Amount
Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) and settlement of defined benefit plan.
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Settlement, Reclassification Adjustment from AOCI, before Tax
Antidilutive securities excluded from computation of earnings per share (in shares)
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount
Dry-docking and Ocean-Going Vessels [Abstract]
Drydocking on Ocean-Going Vessels [Abstract]
Commitment amount
Term of the guarantee or each group of financial instruments used to support performance by the company and its subsidiaries in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
Term of Instrument Under Guarantor Obligations
Guarantor obligations, expiration period
Allowance for doubtful accounts
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Allowance for Doubtful Accounts
Impairment of Intangible Assets (Excluding Goodwill), Total
Impairment of intangible assets other than goodwill
2023
Schedule of Long-term Debt Instruments [Table]
Cumulative Effect, Period of Adoption [Axis]
Accounts payable
Accounts payable and accrued liabilities
Maturity Date
Debt Instrument, Maturity Date
Interest paid
Interest paid
Environmental Remediation Site [Domain]
Effective income tax rate
Effective Income Tax Rate Reconciliation, Percent
Number of spills at the site to be declared as a Superfund site.
Site Contingency Number Of Spills
Number of spills
Total U.S. State
State and Local Income Tax Expense (Benefit), Continuing Operations
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Total
Amount excluded on unamortized debt discounts and issuance costs
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.
Significant Accounting Policies [Line Items]
Details of Inventories
Current Fiscal Year End Date
Restricted Stock Unit Activity [Abstract]
RSU Activity [Abstract]
Increase (decrease) in cash and cash equivalents
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect
Other Equipment [Member]
Other Machinery and Equipment [Member]
Details of inventories [Abstract]
Expected timing of satisfaction, period
Operating lease cost
Operating Lease, Cost
Customer Relationships [Member]
Customer Relationships [Member]
Amounts Recognized in Accumulated Other Comprehensive Income
Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year [Table Text Block]
Other Comprehensive Income (Loss)
Segment Data
Segment Reporting Disclosure [Text Block]
Increase (Decrease) in Other Operating Assets, Total
Other assets
Increase (Decrease) in Other Operating Assets
Other
Deferred Tax Assets, Other
Line Of Credit [Member]
Credit Line [Member]
Line of Credit [Member]
Noncontrolling Interests [Member]
Noncontrolling Interest [Member]
Internal Revenue Service (IRS) [Member]
Refers to the segment of business related maritime transport is the shipment of goods (cargo) and people by sea and other waterways.
Marine Transportation Segment [Member]
Marine Transportation Segment [Member]
Buildings [Member]
Building [Member]
Disaggregation of Revenue [Table]
Debt instrument, frequency of periodic payment
ASSETS
Assets [Abstract]
Impairment Effects on Earnings Per Share [Table]
Income taxes payable
Increase (Decrease) in Income Taxes Payable
Amount that would impact the effective tax rate, if recognized
Validity period of contract with customers.
Range Of Renewal Options Under Term Contracts
Range of renewal options under term contracts
Energy Storage System [Member]
Energy Storage System [Member]
Energy storage system [Member]
Refers to percentage of pension plan defined benefit plan cost increase limit during the period.
Pension Plan Defined Benefit Plan Cost Increase Limit Percentage
Pension plan defined benefit plan cost increase limit percentage
Noncontrolling interests
Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance
Stockholders' Equity Attributable to Noncontrolling Interest, Beginning Balance
Stockholders' Equity Attributable to Noncontrolling Interest, Total
Noncontrolling interests
Settlements
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total
Property and equipment
2022
Lessee, Operating Lease, Liability, to be Paid, Year One
Accounts Payable, Current, Total
Accounts payable
Accounts Payable, Current
Restricted Stock Award Activity [Abstract]
Restricted Stock Award Activity [Abstract]
Total other comprehensive income, Income Tax (Provision) Benefit
Other Comprehensive Income (Loss), Tax, Total
Other Comprehensive Income (Loss), Tax
Debt Instrument, Name [Domain]
Long term debt, face amount
Debt Instrument, Face Amount
Litigation Status [Axis]
Common stock, par value per share (in dollars per share)
Revenue Recognition
Revenue from Contract with Customer [Policy Text Block]
Actuarial losses, Gross Amount
Recognition of actuarial loss
Recognition of actuarial gain
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax
Additions based on tax positions related to the current year
Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions
Louisiana [Member]
State and Local Jurisdiction [Member]
Weighted average common stock outstanding - basic (in shares)
Weighted Average Number of Shares Outstanding, Basic
Beginning balance (in shares)
Ending balance (in shares)
Shares, Outstanding
Range of term contracts
Revenue Derived From Term Contracts Maturity Period
Refers to the period of revenue derived form the term contracts maturity.
Additional paid-in capital
Additional Paid in Capital, Common Stock, Ending Balance
Additional Paid in Capital, Common Stock, Beginning Balance
Additional paid-in capital
Information about Plan Assets [Abstract]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Components of net periodic benefit cost [Abstract]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Current
Current
Current Income Tax Expense (Benefit)
Environmental Liabilities
Environmental Costs, Policy [Policy Text Block]
The amount lease termination expense.
Operating Lease Termination Expense
Lease cancellation costs
Lease cancellation costs
Earnings (loss) before taxes on income
Segment profit (loss)
Earnings (loss) before taxes on income
Document Type
Taxes, Miscellaneous, Total
Taxes, other than on income
Taxes, Miscellaneous
United States [Member]
Company's provision for taxes on income varied from the statutory federal income tax rate [Abstract]
Periodic payment, interest
Secured Debt [Member]
Operating lease liabilities - less current portion
Operating lease liabilities - less current portion
Property and equipment:
Property, Plant and Equipment, Net [Abstract]
Thereafter
Net Periodic Benefit Cost
Schedule of Defined Benefit Plans Disclosures [Table Text Block]
Total current assets
Assets, Current
Provision (credit) for doubtful accounts
Accounts Receivable, Credit Loss Expense (Reversal)
Unsecured Debt [Member]
Disaggregation of Revenue [Line Items]
This is the total range, encompassing the minimum exercise price amount, and the maximum exercise price amount. Its child Members should disaggregate the individual tranches of price ranges.
Total Exercise Price Range [Member]
Full Exercise Price Range [Member]
Represents the period of amortization of shipyard costs.
Period of amortization of shipyard costs
Period of amortization of shipyard costs
Number of shares of common stock determined by relating the portion of time within a reporting period that common shares have been issued and outstanding to the total time in that period.
Weighted average common stock issued and outstanding
Weighted average common stock issued and outstanding (in shares)
Rate of compensation increase
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase
Stock Options [Member]
Long-term Debt, Type [Domain]
Deferred
Deferred Federal Income Tax Expense (Benefit)
Weighted Average Remaining Contractual Life
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term
Tabular disclosure of benefits expected to be paid by or contributed to pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter.
Schedule of Expected Cash Flows [Table Text Block]
Expected Cash Flows for the Defined Benefit Plans and Postretirement Benefit Plan
Total Provision (benefit) for taxes on income
(Provision) benefit for taxes on income
Benefit (provision) for taxes on income
Total Provision (benefit) for taxes on income
Income Tax Expense (Benefit)
Actuarial losses, Income Tax (Provision) Benefit
Actuarial gains (losses), Income Tax (Provision) Benefit
Leases [Abstract]
Represents portland Harbor Superfund Site.
Portland Harbor Superfund Site [Member]
Principles of Consolidation
Consolidation, Policy [Policy Text Block]
Loss Contingencies [Line Items]
Provision (benefit) for taxes on income [Abstract]
Provision for taxes on income [Abstract]
Provision (benefit) for taxes on income [Abstract]
Coastal Transportation [Member]
Refers to coastal transportation of refined petroleum products and black oil.
Coastal Transportation [Member]
Nonvested balance end of period (in shares)
Nonvested balance beginning of period (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number
Credit line due June 30, 2021 [Member]
Revolving Credit Facility Due June Thirty Two Thousand Twenty One [Member]
Refers to revolving credit facility debt instruments.
Expected long-term rate of return on plan assets
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Total
Operating loss carryforwards
Deferred Tax Assets, Operating Loss Carryforwards
Current
Current State and Local Tax Expense (Benefit)
Segment Reporting Information, by Segment
Plan Name [Axis]
Accumulated depreciation
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Beginning Balance
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Total
Accumulated depreciation
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment
Forfeited or expired (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period
Current liability
Liability, Defined Benefit Plan, Current
operating leases related to weighted average discount rate and weighted average remaining lease term.
Operating Leases, Weighted Average Discount Rate and Remaining Lease Term [Table Text Block]
Operating Leases, Weighted Average Discount Rate and Remaining Lease Term
Impairments and Other Charges
Asset Impairment Charges [Text Block]
Payments to Acquire Businesses, Net of Cash Acquired, Total
Acquisitions of businesses and marine equipment, net of cash acquired
Payments to Acquire Businesses, Net of Cash Acquired
Deferred
Provision (benefit) for deferred income taxes
Provision for deferred income taxes
Deferred
SERP [Member]
Supplemental Employee Retirement Plan [Member]
Total lease cost
Lease, Cost
Inventories - at lower of average cost or net realizable value
Inventories - net
Inventory, Net
Refers to the entity that is being acquired or purchased in a merger or acquisition.
Savage Inland Marine, LLC [Member]
Savage Inland Marine, LLC [Member]
The amount of operating lease right-of-use assets recognized as of the acquisition date.
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Operating Lease Right-of-Use Assets
Operating lease right-of-use assets
Outstanding at Period Start (in dollars per share)
Outstanding at Period End (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price
Cash flows from operating activities:
Oil and Gas [Member]
Other
Deferred Tax Liabilities, Other
Foreign [Abstract]
Collision with M/S Summer Wind [Member]
HAWAII
HAWAII
Refers to a bank note payable.
Bank Note Payable [Member]
Bank Note Payable [Member]
Future Minimum Lease Payments under Operating Leases
Lessee, Operating Lease, Liability, Maturity [Table Text Block]
Operating Loss Carryforwards [Table]
Earnings Per Share, Diluted, Total
Diluted (in dollars per share)
Diluted (in dollars per share)
Refers to the senior notes debt instruments.
Senior Notes Series B Due February Twenty Seven Two Thousand Twenty Three [Member]
Senior Notes Series B Due February 27, 2023 [Member]
3.29% Senior Notes Due February, 27 2023 [Member]
Earnings Per Share [Abstract]
Impairment Effects on Earnings Per Share [Line Items]
Proceeds from Lines of Credit, Total
Borrowings on bank credit facilities
Refers to the amount related to amortization of unearned compensation.
Amortization of unearned compensation
Amortization of unearned share-based compensation
2023
Lessee, Operating Lease, Liability, to be Paid, Year Two
Total liabilities
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities
Net earnings (loss) attributable to Kirby
Net earnings (loss) attributable to Kirby
Net Income (Loss) Attributable to Parent
Treasury Stock
Repurchase Agreements, Valuation, Policy [Policy Text Block]
Consolidated [Abstract]
Effective Income Tax Rate Reconciliation
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]
Summary of Significant Accounting Policies
Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block]
Concentrations of Credit Risk
Concentration Risk, Credit Risk, Policy [Policy Text Block]
Intangible assets amortization period
Finite-Lived Intangible Asset, Useful Life
Weighted average discount rate
Document Fiscal Period Focus
Summary of Significant Accounting Policies [Abstract]
Current
Environmental Remediation Site [Axis]
Disclosure of accounting policy for entity's ocean-going vessels are subject to regulatory dry docking requirements after certain periods of time to be inspected, and have planned major maintenance performed.
Dry Docking Requirements [Policy Text Block]
Drydocking on Ocean-Going Vessels
Accumulated Other Comprehensive Income (Loss), Net of Tax, Total
Accumulated other comprehensive income - net
Accumulated Other Comprehensive Income (Loss), Net of Tax
Entity Address, Address Line One
Intrinsic value of stock options exercised
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value
Outstanding at Period End (in shares)
Outstanding at Period Start (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number
Refers to amount of fair value of options granted during the period.
Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Fair Value
Fair value of stock options granted
One-time deferred tax provision
One-time deferred tax provision
One-time deferred tax provision
A claim for damages that is likely to be made and for which it is reasonably possible that there will be an unfavorable outcome, such as a likelihood that lawsuits from parties as yet unidentified will be filed alleging injury from using a product when other parties have successfully sued the entity for such use.
Unasserted Claim 1 [Member]
Struck by LPG Tanker, the Genesis River [Member]
Insurance premiums and claims are reviewed by the entity's for their validity and then paid out to the insured or requesting party (on behalf of the insured) once approved.
Insurance Premiums And Claims
Insurance premiums and claims
Retirement Plan Type [Axis]
Total current liabilities
Liabilities, Current
Accumulated amortization
Finite-Lived Intangible Assets, Accumulated Amortization
First year
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year
Net earnings (loss)
Net earnings (loss)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest
Foreign currency translation, Gross Amount
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax, Total
Foreign currency translation adjustments, Gross Amount
Entity Address, Postal Zip Code
Damages and Assessment Cost
Damages and assessment cost.
Debt Instrument, Fair Value Disclosure, Total
Fair value
Current year actuarial loss
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax
Refers to inland tank barges equipped with tanks that may carry any one of a great variety of liquid commodities, such as petroleum and petroleum products, chemicals, and fertilizers.
Inland Tank Barges [Member]
Inland Tank Barges [Member]
Treasury Stock, Shares, Ending Balance
Treasury Stock, Shares, Beginning Balance
Treasury Stock, Shares, Total
Treasury stock, shares (in shares)
Tax withholdings on equity award vesting (in shares)
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation
Aggregate Intrinsic Value, Options Outstanding
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value
Total lease payments
Liabilities for operating leases
Products and Services [Domain]
Other long-term liabilities
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other
Other income (expense) included in net income that results in no cash inflows or outflows in the period. Includes noncash adjustments to reconcile net income (loss) to cash provided by (used in) operating activities that are not separately disclosed.
Amortization of Major Maintenance Costs
Amortization of major maintenance costs
Net cash provided by operating activities
Net Cash Provided by (Used in) Operating Activities
Litigation Status [Domain]
2026
Amount of amortization expense for assets and liabilities, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
Finite-Lived Intangible Assets and Liabilities, Amortization Expense, Year Five
Credit facility, expiration date
Line of Credit Facility, Expiration Date
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Refers to amount of general corporate expenses.
General corporate expenses
General corporate expenses
Equity Components [Axis]
Lease Cost
Current assets:
Current assets:
Variable lease cost
Entity Registrant Name
Accumulated impairment and amortization
Accumulated impairment and amortization
Goodwill, Impaired, Accumulated Impairment Loss
Inland Transportation [Member]
Refers to inland transportation of petrochemical feedstock, chemicals, pressurized products, refined petroleum products, certain black oil, agricultural chemicals and black oil, such as asphalt.
Inland Transportation [Member]
Assets other than goodwill that contribute to the future cash flows of both the cash-generating unit under review and other cash-generating units.
General corporate assets
Guarantor Obligations, Nature [Domain]
Amount after allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards federal for which it is more likely than not that a tax benefit will be realized.
Operating Loss Carryforwards, Net of Valuation Allowance, Federal
Operating loss carryforwards, net of valuation allowance
Share based Compensation Plans Combined Disclosure [Abstract]
Share-based Compensation Plans Combined Disclosure [Abstract]
Share based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Exercisable Options [Abstract]
Options Exercisable [Abstract]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill, Total
Intangible assets acquired
Other intangibles
Represents information of fourth price range of option prices pertaining to options granted.
Fourth Price Range [Member]
Fourth Price Range [Member]
The company which is self-insurance not-for-profit organization authorized by the U.S. Department of Labor as a longshore worker's compensation insurance provider.
Signal Mutual Indemnity Association Ltd [Member]
Signal [Member]
Cash paid during the period [Abstract]
Cash paid (received) during the period:
Term of grant
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period
Other Intangibles [Abstract]
Entity Interactive Data Current
Entity Address, City or Town
Underlying Asset Class [Domain]
State operating loss deferred tax assets
Equity:
Equity:
International Equity Securities [Member]
Defined Benefit Plan, Equity Securities, Non-US [Member]
Related Party [Abstract]
Unusual or Infrequent Item, or Both [Domain]
Estimated option term
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax, Total
Pension and postretirement benefits
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax
Trading Symbol
Related Party Transactions
Incremental Common Shares Attributable to Share-based Payment Arrangements, Total
Dilutive effect of stock options and restricted stock units (in shares)
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements
Amount of accrued liabilities expected to be recognized as such within one year or the normal operating cycle, if longer, assumed at the acquisition date.
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accrued Liabilities
Accrued liabilities
Gain on disposition of assets
Gain on disposition of assets
Gain on disposition of assets
Gain (loss) on disposition of assets
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property
Cash flows from investing activities:
Net Cash Provided by (Used in) Investing Activities [Abstract]
Less: imputed interest
Lessee, Operating Lease, Liability, Undiscounted Excess Amount
Concentration Risk Type [Axis]
Total equity
Beginning balance
Ending balance
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest
Restricted Stock Award Activity
Share-based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block]
Other Intangibles
Weighted average amortization period of unfavorable contracts in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
Weighted Average Useful Life, Unfavorable Contracts
Weighted average amortization period of unfavorable contracts
Capital expenditures included in accounts payable
Current and future cash outflow to pay for purchases of fixed assets that have occurred.
Capital Expenditures Incurred, Paid and Not yet Paid
Capital expenditures included in accounts payable
Trade, allowance for doubtful accounts
Accounts Receivable, Allowance for Credit Loss, Current
Canada [Member]
Foreign [Member]
Income taxes payable
Accrued Income Taxes, Current
Loss contingency, settlement charges
Amount after amortization of liabilities, excluding financial liabilities and goodwill, lacking physical substance with a finite life.
Finite Lived Intangible Liabilities Net
Other intangible liabilities - net
Local Phone Number
Plan Asset Categories [Domain]
Stockholders' Equity Attributable to Parent, Ending Balance
Stockholders' Equity Attributable to Parent, Beginning Balance
Total Kirby stockholders' equity
Stockholders' Equity Attributable to Parent
Payment of debt issue costs
Payments of Debt Issuance Costs
Subsequent Event Type [Axis]
Quarterly Results
Quarterly Financial Information [Table Text Block]
Balance at end of year
Balance at beginning of year
Unrecognized Tax Benefits
Higman pension plan for 2020 year.
Plan 2020 [Member]
Plan 2020 [Member]
Operating cash outflow from operating leases
Operating cash outflow from operating leases
Repayments of Long-term Debt, Total
Payments on long-term debt
Payments on long-term debt
Repayments of Long-term Debt
Statistical Measurement [Axis]
Amounts recognized in accumulated other comprehensive income [Abstract]
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Other changes in benefit obligations recognized in other comprehensive income [Abstract]
Entity Small Business
Loss Contingency, Nature [Domain]
Insurance accruals
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Self Insurance
Fair Value Hierarchy and NAV [Domain]
Target allocations
Credit Facility [Axis]
Long-term Debt, Excluding Current Maturities, Total
Long-term debt, net - less current portion
Long-term Debt, Excluding Current Maturities
Variable Rate [Axis]
Deferred Tax Assets and Liabilities
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]
Total other comprehensive income, Gross Amount
Other Comprehensive Income (Loss), before Tax
Non-cash investing activity: [Abstract]
Non-cash investing activity:
Accrued liabilities:
Accrued Liabilities, Current [Abstract]
Impairment of Long-Lived Assets and for Long-Lived Assets to Be Disposed Of
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]
Variable Rate [Domain]
Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of before tax from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.
Tax Cuts and Jobs Act, Other Comprehensive (Income) Loss, Reclassification from AOCI to Retained Earnings, Before Tax
Reclassification to retained earnings of stranded tax effects from tax reform, Gross Amount
Intersegment Eliminations [Member]
Debt Instrument, Carrying Value and Fair Value [Abstract]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Estimated useful lives of the individual assets
Accounts Receivable [Abstract]
Accounts receivable
Accounts receivable
Business Acquisition [Axis]
Segment Data [Abstract]
Refers to the number of maritime (seagoing) vessels acquired.
Number of Maritime Vessels Acquired
Number of maritime vessels acquired
Number of maritime vessels acquired
ASU 2014-09 [Member]
Accounting Standards Update 2014-09 [Member]
Deferred tax assets tax deferred expense of non current unrealized loss on defined benefit plans.
Deferred Tax Assets Tax Deferred Expense Of Non Current Unrealized Loss On Defined Benefit Plans
Unrealized loss on defined benefit plans
Fair Value Measurements
Capitalized interest excluded from interest expense
Reconciliation of the beginning and ending amount of the liability for unrecognized tax benefits [Roll Forward]
A credit facility arrangement that is repayable in quarterly installments in increasing percentages of the original principal amount of the loan.
Term Loan Facility [Member]
Term Loan [Member]
Weighted average amortization period for intangible assets and liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
Intangible Assets and Liabilities Weighted Average Amortization Period
Weighted average amortization period for intangible assets and liabilities
Other Postretirement Benefits [Member]
Other Postretirement Benefits Plan [Member]
Operating lease liabilities, including current portion
Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Lease Obligation
Net Income (Loss) Attributable to Parent [Abstract]
Net Income (Loss) Attributable to Parent [Abstract]
Return of investment to noncontrolling interests and other
Amount payment to noncontrolling interest for return of investment during the period.
Payments to Noncontrolling Interests for Return of Investment
Granted (in dollars per share)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price
Unusual or Infrequent Item, or Both [Axis]
Tabular disclosure of the profit or loss and total assets for other segment information.
Schedule Of Other Segment Reporting Information By Segment [Table Text Block]
Other Segment Reporting Information
2005 Stock and Incentive Plan [Member]
Stock and Incentive Plan 2005 [Member]
Represents to stock and incentive plan of the equity-based compensation arrangement plan.
Weighted-Average Assumption Used to Determine Benefit Obligation and Net Periodic Benefit Cost
Defined Benefit Plan, Assumptions [Table Text Block]
Related Party Transaction [Line Items]
Revenues [Abstract]
Thereafter
Lessee, Operating Lease, Liability, to be Paid, after Year Five
Plan Name [Domain]
Deferred tax assets [Abstract]
Components of Deferred Tax Assets [Abstract]
Goodwill
Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block]
2022
Income Tax Authority [Axis]
Aggregate contributions to the plans
Defined Contribution Plan, Cost
Expiration dates, operating loss carryforwards
Operating Loss Carryforwards, Expiration Date
Change in Benefit Obligation
Schedule of Changes in Projected Benefit Obligations [Table Text Block]
State and local taxes, net of federal benefit
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent
Amortization of Intangible Assets, Total
Amortization of intangible assets
Percentage of inland revenue from movement of products under term contracts.
Percentage Of Inland Revenue
Percentage of inland revenue
Refers to the senior notes debt instruments.
Senior Notes Due March One Two Thousand Twenty Eight [Member]
Senior Notes Due March 1, 2028 [Member]
4.2% Senior Notes Due March 1, 2028 [Member]
Settlement Agreement [Member]
Settlement agreement.
Settlement Agreement [Member]
Number of vessels damaged in collision resulting in fuel oil discharge.
Number of vessels damaged in collision resulting in fuel oil discharge
Number of years net operating losses are carried back.
Number of Years Net Operating Losses Carried Back
Number of years net operating losses carried
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
This element represents the total of unrecognized tax benefits including interest expense recognized for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity and the amount of statutory penalties in the period in which the entity claims or expects to claim a tax position, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.
Unrecognized Tax Benefits Including Income Tax Penalties and Interest
Unrecognized tax benefits including interest and penalties
The service period of eligible participants of the employee pension plan who will be grandfathered and not be impacted by the amendment to the pension plan.
Employee Pension Plan, Grandfathered Participants, Service Period
Service period of participants not impacted by pension plan amendment
Amortization of actuarial loss
Amortization of actuarial gain
Defined Benefit Plan, Amortization of Gain (Loss)
Total recognized in other comprehensive income
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax
Interest Expense, Total
Interest expense
Interest Expense
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price, Ending Balance
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price, Beginning Balance
Weighted Average Exercise Price, Options Outstanding (in dollars per share)
Years open to audit under the statute of limitations
Operating losses tax year
Debt Instrument, Unamortized Discount, Total
Original issue discount
Unamortized debt discounts and issuance costs
Outstanding and Exercisable Stock options [Abstract]
Interest cost
Interest cost
Defined Benefit Plan, Interest Cost
Balance (gross)
Balance (gross)
Goodwill, Gross
Schedule detailing all significant accounting policies of the reporting entity.
Significant Accounting Policies [Table]
Share-based Payment Arrangement, Noncash Expense, Total
Amortization of unearned share-based compensation
Share-based Payment Arrangement, Noncash Expense
Prepaid expenses and other current assets
Prepaid expenses and other current assets
RSU Activity
Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]
Number of reporting units
Number of Reporting Units
Stock Option Activity
Share-based Payment Arrangement, Option, Activity [Table Text Block]
Property, Plant and Equipment, Type [Domain]
Related Party Transactions [Abstract]
Carrying value
Long-term Debt
Inventories [Abstract]
Segment Reporting Information [Line Items]
Refers to the entity that is being acquired or purchased in a merger or acquisition.
Savage Inland Marine, LLC and Convoy Servicing Company and Agility Fleet Services, LLC [Member]
Savage Inland Marine, LLC and Convoy [Member]
Distribution and services - A component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.
Distribution And Services [Member]
Distribution and Services [Member]
Distribution and Services Segment [Member]
Current
Current Federal Tax Expense (Benefit)
Debt Securities [Member]
Defined Benefit Plan, Debt Security [Member]
Inventories
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory
U.S. Federal [Abstract]
Federal Income Tax Expense (Benefit), Continuing Operations [Abstract]
Net cash provided by (used in) financing activities
Net Cash Provided by (Used in) Financing Activities
Contingencies and Commitments [Abstract]
Represents information of second price range of option prices pertaining to options granted.
Second Price Range [Member]
Second Price Range [Member]
Right-of-use assets obtained in exchange for lease obligations
Right-of-use assets obtained in exchange for lease obligations
Vested (in dollars per share)
Total assets
Total assets
Assets
Payments on bank credit facilities
Repayments of Lines of Credit
Reconciliation of Liability for Unrecognized Tax Benefits
Summary of Income Tax Contingencies [Table Text Block]
leases
Lessee, Operating Leases [Text Block]
Exercised (in shares)
Stock option exercises (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total
Accrued liabilities for payment of interest and penalties
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued
Statement [Line Items]
Total liabilities and equity
Liabilities and Equity
Property, Maintenance and Repairs [Abstract]
CONSOLIDATED STATEMENTS OF CASH FLOWS [Abstract]
Additional Paid-in Capital [Member]
Additional Paid-in Capital [Member]
Title of 12(b) Security
Comprehensive income (loss) attributable to Kirby
Comprehensive Income (Loss), Net of Tax, Attributable to Parent
Long-term Line of Credit, Total
Credit facility, amount outstanding
Credit facility, amount outstanding
Level 3 [Member]
Level 3 [Member]
Debt Instrument [Line Items]
Quarterly Results (Unaudited) [Abstract]
Entity Well-known Seasoned Issuer
Operating Loss Carryforwards [Line Items]
Period referring customer relationship maintained by some of the manufacturing and refining customers.
Customer Relationship Period
Customer relationship period
Tax withholdings on equity award vesting
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation
Letters Of Credit [Member]
Standby Letters of Credit [Member]
Equity Award [Domain]
Prepaid expenses and other current assets
Prepaid expenses
Return of investment to noncontrolling interests
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders
Refers to the amount of accruals for revenues earned included in accounts receivable.
Accruals For Revenues Earned Included In Accounts Receivable
Accruals for revenues earned included in accounts receivable
Fair Value Hierarchy and NAV [Axis]
Refers to the amount of receivables from insurance companies to cover claims in excess included in accounts receivable.
Receivables From Insurance Companies To Cover Claims In Excess Included In Accounts Receivable
Receivables from insurance companies to cover claims in excess included in accounts receivable
The average age of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.
Property, Plant and Equipment, Average Age
Average age of property
Funded Status at End of Year
Schedule of Net Funded Status [Table Text Block]
Other comprehensive income (loss), net of taxes:
Other comprehensive loss, net of taxes:
Goodwill acquired
Business Acquisition, Goodwill, Expected Tax Deductible Amount
Level 1 [Member]
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Total
Deferred compensation
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total
Issuance of stock for equity awards, net of forfeitures (in shares)
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures
Aggregate Payments due on the Long-Term Debt
Schedule of Maturities of Long-term Debt [Table Text Block]
2025
Lessee, Operating Lease, Liability, to be Paid, Year Four
Debt instrument, interest rate, stated percentage
Interest rate
Debt Instrument, Interest Rate, Stated Percentage
Higman pension plan for 2019 year.
Plan 2019 [Member]
Plan 2019 [Member]
Defined Benefit Plan, Asset Categories [Axis]
Restricted Stock [Member]
Undistributed Earnings Reallocated To Restricted Shares.
Undistributed Earnings Reallocated To Restricted Shares
Undistributed earnings reallocated to restricted shares
Nonoperating Income (Expense), Total
Other income
Nonoperating Income (Expense)
Deferred Tax Liabilities, Net, Total
Net deferred tax liabilities
Deferred Tax Liabilities, Net
Stock-Based Compensation
Share-based Payment Arrangement, Director [Policy Text Block]
Accounts Receivable
Receivable [Policy Text Block]
Granted (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross
Entity Current Reporting Status
Non-cash pre-tax impairment charge
Non-cash write-down
Impairments and other charges
Impairment of Long-Lived Assets to be Disposed of
Revenues
Revenue from Contract with Customer [Text Block]
Investment Type [Axis]
Entity Voluntary Filers
Real Estate Investment [Member]
Scenario [Domain]
Documents Incorporated by Reference [Text Block]
Granted (in dollars per share)
Weighted average grant date fair value, granted (in dollars per share)
Underlying Asset Class [Axis]
Accrued Insurance [Abstract]
Amount of deferred tax liability attributable to taxable temporary differences from deferred state taxes.
Deferred Tax Liabilities State Taxes
Deferred state taxes
Bank notes payable
Bank notes payable
Cash and equity securities.
Cash and Equity Securities [Member]
Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table]
Retirement Plans [Abstract]
Other Supplemental Information about Operating Leases [Abstract]
Other Supplemental Information about Operating Leases [Abstract]
Gross benefits paid
Defined Benefit Plan, Benefit Obligation, Benefits Paid
Deferred tax assets
U.S. Equity Securities [Member]
Defined Benefit Plan, Equity Securities, US [Member]
Deferred
Central Pension Fund of the International Union of Operating (CPF) is a defined benefit plan providing retirees with a predetermined monthly retirement benefit upon reaching a specific age. The retirement benefit paid to a retiree is typically calculated using a formula which often employs years of credited service under the plan and salary information. The retirement benefit is typically payable to the employee upon attainment of their normal retirement age for the remainder of his/her lifetime. Benefits under this type of plan are often referred to as accrued benefits. This type of plan does not maintain individual accounts for employees.
Central Pension Fund of the International Union of Operating [Member]
CPF [Member]
Expected benefit payments (gross) [Abstract]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
Accumulated Other Comprehensive Income [Member]
AOCI Attributable to Parent [Member]
Represents information of third price range of option prices pertaining to options granted.
Third Price Range [Member]
Third Price Range [Member]
Auditor Firm ID
Long-term Debt, Type [Axis]
Asset allocations
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage
Represents maximum entity's contribution limit to the concerned pension trust during the reporting period.
Defined Benefit Plan Maximum Contribution Limit
Maximum contribution limit
Acquisition related costs
Acquisition related costs
Tax benefit from restricted stock vesting during the reporting period.
Tax Benefit From Restricted Stock Vesting
Tax benefit from restricted stock vesting
Auditor Name
Cumulative Effect, Period of Adoption, Adjustment [Member]
Share based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Outstanding Options [Abstract]
Options Outstanding [Abstract]
Earnings Per Share, Basic, Total
Basic (in dollars per share)
Basic (in dollars per share)
Open Tax Year [Abstract]
Open Tax Year [Abstract]
2025
Amount of amortization expense for assets and liabilities, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
Finite-Lived Intangible Assets and Liabilities, Amortization Expense, Year Four
Service cost
Service cost
Defined Benefit Plan, Service Cost
Refers to number of barge slips during the period.
Number of barge slips
Number of barge slips
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total
Income tax penalties and interest recognized
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense
Minimum [Member]
Minimum [Member]
Liability, Defined Benefit Plan, Noncurrent, Total
Long-term liability
Liability, Defined Benefit Plan, Noncurrent
Stock option exercises
Total Foreign
Foreign Income Tax Expense (Benefit), Continuing Operations
Other assets
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets
Savage acquisition
Cash paid for acquisition
Cash paid for acquisition
Rate of compensation increase
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase
Employee Stock Award Plan [Abstract]
Stock Award Plan Information [Abstract]
Expected return on plan assets
Defined Benefit Plan, Expected Return (Loss) on Plan Assets
Percentage of the net operating loss carryback from effect of Coronavirus Aid, Relief, and Economic Security (CARES) Act.
Effective Income Tax Rate Reconciliation Cares Act Net Operating Loss Carryback
CARES Act - net operating loss carryback
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Total
Investment in affiliates
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures
Employer contribution
Pension contributions
Defined Benefit Plan, Plan Assets, Contributions by Employer
Granted (in shares)
The company which is not-for-profit that provides global classification services to the marine, offshore and gas industries.
American Bureau of Shipping [Member]
ABS [Member]
Costs incurred and are directly related to generating revenues and generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services, excludes selling, general and administrative expense.
Costs Of Sales And Operating Expenses
Costs of sales and operating expenses
Future Minimum Lease Payments Under Operating Leases [Abstract]
Future Minimum Lease Payments Under Operating Leases [Abstract]
Refers to selling OEM replacement parts and new diesel engines, provides service mechanics and maintains facilities to overhaul and repair diesel engines and ancillary products for marine and on-highway transportation companies, mining and industrial companies. The Company provides engineering and field services, OEM replacement parts and safety-related products to power generation operators and to the nuclear industry, manufactures engine generator and pump packages for power generation operators and municipalities, offers power generation systems customized for specific commercial and industrial applications, and rents equipment including power generation systems, pumps, air compressors, fork lifts and railcar movers.
Commercial and Industrial [Member]
Commercial and Industrial [Member]
Schedule of Business Acquisitions, by Acquisition [Table]
Document Annual Report
Asset Impairment Charges, Total
Impairments and other charges
Impairments and other charges
Asset Impairment Charges
Intrinsic value of restricted stock vesting
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested
Fair Value Assumptions [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Deferred Tax Assets, Valuation Allowance, Total
Valuation allowances
Deferred Tax Assets, Valuation Allowance
Total comprehensive income (loss), net of taxes
Total comprehensive income (loss), net of taxes
Exercise Price Range [Axis]
Schedule of Defined Benefit Plans Disclosures [Table]
Cash flows from financing activities:
Cash flows from financing activities:
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total
Unrecognized compensation cost related to unvested awards
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount
Proceeds from sale of assets
Proceeds from disposition of assets and other
Proceeds from Sale of Productive Assets, Total
Proceeds from disposition of assets and other
Percentage of costal revenue from movement of products under term contracts.
Percentage of coastal revenue
Percentage of costal revenue
Change in plan assets [Roll Forward]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Higman pension plan for 2018 year.
Plan 2018 [Member]
Plan 2018 [Member]
Debt Instrument [Axis]
Impairment
Goodwill impairment charge
Goodwill, Impairment Loss
Entity Filer Category
Accrued insurance liabilities
Accrued Insurance
Taxes on Income
Income Tax, Policy [Policy Text Block]
Finite-Lived Intangible Assets and Liabilities, Estimated Amortization Expense, Fiscal Year Maturity [Abstract]
Intangible Assets and liabilities, Estimated Amortization Expense, Fiscal Year Maturity [Abstract]
Document Fiscal Year Focus
Foreign currency translation, Income Tax (Provision) Benefit
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax, Total
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax
Interest
Interest Payable, Current
Accumulated amount of amortization of liabilities, excluding financial liabilities and goodwill, lacking physical substance with a finite life.
Finite Lived Intangible Liabilities Accumulated Amortization
Accumulated amortization
Asset Allocation
Schedule of Allocation of Plan Assets [Table Text Block]
Changes in Goodwill
Schedule of Goodwill [Table Text Block]
Fair value of stock options granted (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value
Retained earnings
Retained Earnings (Accumulated Deficit), Ending Balance
Retained Earnings (Accumulated Deficit), Beginning Balance
Retained Earnings (Accumulated Deficit), Total
Retained earnings
Taxes on Income
Income Tax Disclosure [Text Block]
Refers to the carrying capacity of tank barges as measured in number of barrels.
Tank Barge Barrel Capacity
Tank barge barrel capacity (in barrels)
Tank barge barrel capacity (in barrels)
Change in benefit obligation [Roll Forward]
Total other assets
Other Assets
Legal form of business company offering limited liability to its owners.
Limited Liability Partnership [Member]
Strasburger & Price, LLP [Member]
Share-based Payment Arrangement, Option, Exercise Price Range, Shares Exercisable, Ending Balance
Share-based Payment Arrangement, Option, Exercise Price Range, Shares Exercisable, Beginning Balance
Number Exercisable (in shares)
Short-term lease cost
Maximum [Member]
Maximum [Member]
Operating Loss Carryforward [Abstract]
Operating Loss Carryforward [Abstract]
Entity Central Index Key
Business Acquisition, Acquiree [Domain]
2026.
2026
Year five
Defined Benefit Plan, Expected Future Benefit Payment, Year Five
Revenues [Abstract]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Changes in Other Comprehensive Income (Loss)
Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block]
Funded status and amount recognized at end of year
Defined Benefit Plan, Funded (Unfunded) Status of Plan
Change in Plan Assets
Schedule of Changes in Fair Value of Plan Assets [Table Text Block]
Cash Equivalents
Cash and Cash Equivalents, Policy [Policy Text Block]
Fair Values of Assets Acquired and Liabilities Assumed
Entity Tax Identification Number
Borrowings and Payments under the Revolving Credit Facility [Abstract]
Long-term Debt [Abstract]
Debt Instruments [Abstract]
Equity Component [Domain]
Actual return on plan assets
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)
Payments for legal settlements
Payments for Legal Settlements
Defined Benefit Plan, Initial Health Care Cost Trend Rate
Defined Benefit Plan, Initial Health Care Cost Trend Rate
Initial rate
Stock price volatility
Segments [Domain]
Income Tax Authority [Domain]
Weighted average period of recognition in years
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition
Consolidation Items [Domain]
Foreign currency translation adjustments, Net Amount
Foreign currency translation adjustments
Long-Term Debt
Long-term Debt [Text Block]
Accounts receivable
Increase (Decrease) in Accounts Receivable
Undistributed Earnings (Loss) Allocated to Participating Securities, Diluted, Total
Undistributed earnings allocated to restricted shares
Undistributed Earnings (Loss) Allocated to Participating Securities, Diluted
Expected employer contributions [Abstract]
Defined Benefit Plan, Expected Future Employer Contributions [Abstract]
Number of companies also named as potentially responsible parties under comprehensive environmental response compensation and liability act.
Site Contingency Number Of Companies Named As Potentially Responsible Parties Under Comprehensive Environmental Response Compensation And Liability Act
Number of other companies also named as Potentially Responsible Parties ("PRPs")
Statement [Table]
Weighted average remaining lease term
Refers to the entity that is being acquired or purchased in a merger or acquisition.
Cenac Marine Services, LLC [Member]
Cenac Marine Services, LLC [Member]
Selling, General and Administrative Expense, Total
Selling, general and administrative
Refers to the equipment related maritime transport is the shipment of goods (cargo) and people by sea and other waterways.
Marine Transportation Equipment [Member]
Marine Transportation Equipment [Member]
Entity File Number
Share-Based Compensation Arrangement By Share-Based Payment Award [Line Items]
Represents information of first price range of option prices pertaining to options granted.
First Price Range [Member]
First Price Range [Member]
Accumulated other compensation income
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax
Retained Earnings [Member]
Retained Earnings [Member]
Type of Adoption [Domain]
Adjustments for New Accounting Pronouncements [Axis]
Revenue from Contract with Customer, Excluding Assessed Tax, Total
Revenues
Revenues by major source
Total revenues
Gross benefits paid
Defined Benefit Plan, Plan Assets, Benefits Paid
Increase (Decrease) in Accounts Payable, Total
Accounts payable
Increase (Decrease) in Accounts Payable
Inventory
Inventories
Inventory Disclosure [Text Block]
Current liabilities:
Current liabilities:
Stock Award Plans
Share-based Payment Arrangement [Text Block]
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax, Total
Current year actuarial loss (gain)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax
Increase (decrease) in cash flows resulting from changes in:
Increase (Decrease) in Operating Assets [Abstract]
Performance Bonds [Member]
Debt Securities Payable [Member]
Subsequent Events [Member]
Pension and postretirement benefits [Abstract]
Small powerful boat designed for towing or pushing larger vessels.
Tugboats [Member]
Offshore Tugboats [Member]
Net earnings (loss) per share attributable to Kirby common stockholders:
Net earnings (loss) per share attributable to Kirby common stockholders [Abstract]
Net earnings (loss) per share attributable to Kirby common stockholders:
Contingencies and Commitments
Commitments and Contingencies Disclosure [Text Block]
Operating Lease, Liability, Total
Operating lease liabilities
Operating Lease, Liability
Discount rate
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate
Number of single customers who account for more than 10 percent of segment revenues.
Number of major customers accounting more than ten percent of revenue
Number of single customers accounting more than 10% of segment revenue
Common Stock [Member]
Property, Plant and Equipment, Gross, Ending Balance
Property, Plant and Equipment, Gross, Beginning Balance
Property and equipment
Property, Plant and Equipment, Gross
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table]
Entity Public Float
Land, buildings and equipment
Property, Plant and Equipment, Other, Gross
Property, Maintenance and Repairs
Property, Plant and Equipment, Planned Major Maintenance Activities, Policy [Policy Text Block]
Retirement Plan Type [Domain]
Cover [Abstract]
Credit Facility [Domain]
Nonvested balance beginning of period (in dollars per share)
Nonvested balance end of period (in dollars per share)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value
Goodwill acquired
Deferred tax liabilities [Abstract]
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY [Abstract]
Tax benefit from stock options exercised
Deferred Tax Expense from Stock Options Exercised
Total recognized in net periodic benefit cost and other comprehensive income
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax
Stock Award Plans [Abstract]
Accrued and other liabilities
Increase (Decrease) in Other Accounts Payable and Accrued Liabilities
Refers to pressure tank barges.
Pressure Tank Barges [Member]
Inland Pressure Tank Barges [Member]
A mutual marine protection and indemnity organization that provides protection and indemnity insurance for third party liabilities and expenses arising from vessel operations.
UK Protection & Indemnity Association [Member]
Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of net of tax from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.
Tax Cuts and Jobs Act, Other Comprehensive (Income) Loss, Reclassification from AOCI to Retained Earnings, Net of Tax
Reclassification to retained earnings of stranded tax effects from tax reform, Net Amount
Benefit obligations
Benefit obligation at end of year
Benefit obligation at beginning of year
Defined Benefit Plan, Benefit Obligation
RSUs [Member]
Property, Plant and Equipment, Type [Axis]
Schedule of Segment Reporting Information, by Segment [Table]
Refers to the number of top distributors of off-highway engines.
Number of Top Distributors, Off-highway Engines
Number of off-highway top distributors
Other
Other Accrued Liabilities, Current
Document Transition Report
Proceeds from exercise of stock options
Proceeds from exercise of stock options
Letter of Credit [Member]
Deferred
Deferred Foreign Income Tax Expense (Benefit)
Amount of amortization expense attributable to major maintenance activity costs.
Amortization of Major Maintenance Activity Costs
Recognized amortization of major maintenance costs
Weighted average common stock outstanding - diluted (in shares)
Weighted Average Number of Shares Outstanding, Diluted
Other [Member]
Other Segments [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accrued Insurance
Self Insurance Reserve [Policy Text Block]
Compensation cost
Share-based Payment Arrangement, Expense
Segments [Axis]
CONSOLIDATED BALANCE SHEETS [Abstract]
Deferred Tax Liabilities, Goodwill and Intangible Assets, Total
Goodwill and other intangibles
Deferred Tax Liabilities, Goodwill and Intangible Assets
Dividend yield
Vesting (in shares)
Vested (in shares)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period
Depreciation and amortization
Depreciation, Depletion and Amortization, Total
Depreciation and amortization
Goodwill and other intangibles
U.S. State [Abstract]
Impairment charge
Impairment charge
Defined Benefit Plan, Plan Assets, Amount, Total
Fair value of plan assets
Fair value of plan assets at end of year
Fair value of plan assets at beginning of year
Defined Benefit Plan, Plan Assets, Amount
Lessee, Operating Lease, Liability, to be Paid, Year Five
2026
COVID-19 [Member]
United States income tax statutory rate
Effective income tax rate
Kirby stockholders' equity:
Kirby stockholders' equity:
Reductions for tax positions of prior years
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions
Weighted Average Exercise Price [Abstract]
Stock Appreciation Rights [Member]
Stock Appreciation Rights (SARs) [Member]
Refers to a location
SBA Shipyard Site [Member]
SBA Shipyard Site [Member]
Treasury stock purchases
Treasury Stock, Value, Acquired, Cost Method
Cash and Cash Equivalents [Member]
Defined Benefit Plan, Cash and Cash Equivalents [Member]
The age of eligible participants of the employee pension plan who will be grandfathered and not be impacted by the amendment to the pension plan.
Employee Pension Plan, Grandfathered Participants, Participant Age
Age of plan participants not impacted by pension plan amendment
Amortization of net actuarial loss, Income Tax (Provision) Benefit
Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) and settlement of defined benefit plan.
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Settlement, Reclassification Adjustment from AOCI, Tax
Earnings Per Share
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
Exercised (in dollars per share)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price
Health care cost trend rate [Abstract]
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Increase (Decrease) in Inventories, Total
Inventory
Increase (Decrease) in Inventories
Acquisitions [Abstract]
Business Combination, Separately recognized Transactions, Additional Disclosures [Abstract]
Refers to the senior notes debt instruments.
Senior Notes Series A Due February Twenty Seven Two Thousand Twenty [Member]
Senior Notes Series A Due February 27, 2020 [Member]
2.72% Senior Notes Due February 27, 2020 [Member]
Range of Exercise Prices, upper limit (in dollars per share)
3.51 Series B Notes Due January 19, 2023 [Member]
Three point Five One Series B Notes Due January Nineteen Two Thousand Thirty Three [Member]
Three point five one series b notes due january nineteen two thousand thirty three.
Ultimate rate
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate
2025
2024
Lessee, Operating Lease, Liability, to be Paid, Year Three
Entity Common Stock, Shares Outstanding
A table disclosing the information about earnings (loss) before taxes on income.
Income Tax Disclosure [Table]
Award Type [Axis]
Disaggregation of Revenue [Abstract]
Entity Shell Company
LIABILITIES AND STOCKHOLDERS' EQUITY
Liabilities and Equity [Abstract]
Retirement Plans
Retirement Benefits [Text Block]
Seafarers Pension Trust is a defined benefit plan providing retirees with a predetermined monthly retirement benefit upon reaching a specific age. The retirement benefit paid to a retiree is typically calculated using a formula which often employs years of credited service under the plan and salary information. The retirement benefit is typically payable to the employee upon attainment of their normal retirement age for the remainder of his/her lifetime. Benefits under this type of plan are often referred to as accrued benefits. This type of plan does not maintain individual accounts for employees.
Seafarers Pension Trust [Member]
Seafarers Pension Trust [Member]
ICFR Auditor Attestation Flag
Entity Incorporation, State or Country Code
Earnings (loss) before taxes on income [Abstract]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest [Abstract]
Non Current Deferred Tax Assets And Liabilities [Abstract]
Non-current deferred tax assets and liabilities [Abstract]
Earnings Per Share
Earnings Per Share [Text Block]
Prior service cost (credit)
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax
Unvested RSU Shares [Roll Forward]
LIBOR [Member]
Percentage of costs relate to service costs for leased towing vessels
Estimated percentage of costs related to service costs and other non-lease components.
Percentage of Costs related to Service Costs Estimated
Percentage of costs relate to service costs for leased towing vessels
Treasury stock purchases (in shares)
Treasury Stock, Shares, Acquired
Amendment Flag
Consolidation Items [Axis]
Products and Services [Axis]
Non-compete Agreements [Member]
Weighted average unvested restricted stock (in shares)
Weighted Average Number of Shares, Restricted Stock
Cash and cash equivalents
Cash and Cash Equivalents, at Carrying Value, Ending Balance
Cash and Cash Equivalents, at Carrying Value, Beginning Balance
Cash and Cash Equivalents, at Carrying Value, Total
Cash and cash equivalents
Other income
Other Nonoperating Income
Accounting Standards Adoptions
New Accounting Pronouncements, Policy [Policy Text Block]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Domain]
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent, Total
Other - net
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent
Income taxes paid (refunded), net
Income Taxes Paid, Net, Total
Income Taxes Paid, Net
Long-term debt
Long-term debt
Term loan
Income tax benefit
Share-based Payment Arrangement, Expense, Tax Benefit
Decrease in pension plan projected benefit obligation
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment
Legal services
Legal Fees
Defined Benefit Plan Disclosure [Line Items]
Other Assets, Noncurrent, Total
Other assets
Other Assets, Noncurrent
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Initial Health Care Cost Trend Rate
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Initial Health Care Cost Trend Rate
Initial rate
Loss Contingency Nature [Axis]
Geographical [Domain]
Aggregate Intrinsic Value, Options Exercisable
Settlements
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement, Total
Settlements
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement
Additions for tax positions of prior years
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions
Finite-Lived Intangible Assets, Major Class Name [Domain]
Treasury stock - at cost, 5,361,000 shares in 2021 and 5,434,000 shares in 2020
Treasury Stock, Value, Ending Balance
Treasury Stock, Value, Beginning Balance
Treasury Stock, Value, Total
Treasury Stock, Value
Components of Deferred Tax Assets and Liabilities [Abstract]
Carrying Values and Fair Values of Debt Outstanding
Cumulative Effect, Period of Adoption [Domain]