XML 88 R78.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Retirement Plans, Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost, Other Postretirement Benefits (Details) - Other Postretirement Benefits [Member] | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Weighted average assumptions used to determine net periodic benefit cost [Abstract] |  |  |
Discount rate | 5.50% | 3.00% | 2.80%
Health care cost trend rate [Abstract] |  |  |
Initial rate | 6.50% | 6.25% | 6.50%
Ultimate rate | 5.00% | 5.00% | 5.00%
Years to ultimate | 2029 | 2027 | 2025

X
- Definition Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Initial Health Care Cost Trend Rate + References No definition available. + Details
Name: | kex_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInitialHealthCareCostTrendRate
Namespace Prefix: | kex_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Ultimate Health Care Cost Trend Rate + References No definition available. + Details
Name: | kex_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostUltimateHealthCareCostTrendRate
Namespace Prefix: | kex_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Year ultimate health care cost trend rate is expected to be reached, in CCYY format. + References No definition available. + Details
Name: | kex_DefinedBenefitPlanYearHealthCareCostTrendRateUltimateTrendRate
Namespace Prefix: | kex_
Data Type: | xbrli:gYearItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanAssumedHealthCareCostTrendRatesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |