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Retirement Plans, Information About Plan Assets and Asset Allocation (Details) - USD ($)
12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Information about Plan Assets [Abstract]      
Service period of participants not impacted by pension plan amendment 15 years    
Age of plan participants not impacted by pension plan amendment 50 years    
Service period of participants who are age fifty not impacted by pension plan amendment 10 years    
Fair Value, Inputs, Level 3 [Member]      
Information about Plan Assets [Abstract]      
Fair value of plan assets $ 0 $ 0  
Cash and Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]      
Information about Plan Assets [Abstract]      
Fair value of plan assets   4,800  
Pension Plan [Member]      
Information about Plan Assets [Abstract]      
Pension contributions 8,174,000 906,000  
Fair value of plan assets $ 375,917,000 $ 341,061,000 $ 430,821,000
Expected long-term rate of return on plan assets 6.75% 6.75% 6.75%
Contribution percentage to defined contribution plan 115.00%    
Discount rate 5.50% [1] 3.00%  
Asset Allocation Among Asset Categories [Abstract]      
Asset allocations 100.00% 100.00%  
Pension Plan [Member] | Minimum [Member]      
Information about Plan Assets [Abstract]      
Discount rate   3.00% [1] 2.80%
Pension Plan [Member] | Maximum [Member]      
Information about Plan Assets [Abstract]      
Discount rate   3.10% [1] 2.90%
Pension Plan [Member] | U.S. Equity Securities [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Asset allocations 51.00% 50.00%  
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 50.00%    
Pension Plan [Member] | U.S. Equity Securities [Member] | Minimum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 45.00%    
Pension Plan [Member] | U.S. Equity Securities [Member] | Maximum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 55.00%    
Pension Plan [Member] | International Equity Securities [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Asset allocations 20.00% 20.00%  
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 20.00%    
Pension Plan [Member] | International Equity Securities [Member] | Minimum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 12.00%    
Pension Plan [Member] | International Equity Securities [Member] | Maximum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 28.00%    
Pension Plan [Member] | Debt Securities [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Asset allocations 29.00% 30.00%  
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 30.00%    
Pension Plan [Member] | Debt Securities [Member] | Minimum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 20.00%    
Pension Plan [Member] | Debt Securities [Member] | Maximum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 40.00%    
Pension Plan [Member] | Cash and Cash Equivalents [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Asset allocations 0.00% 0.00%  
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 0.00%    
Pension Plan [Member] | Cash and Cash Equivalents [Member] | Minimum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 0.00%    
Pension Plan [Member] | Cash and Cash Equivalents [Member] | Maximum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage 0.00%    
SERP [Member]      
Information about Plan Assets [Abstract]      
Pension contributions $ 153,000 $ 155,000  
Fair value of plan assets $ 0 $ 0 $ 0
Expected long-term rate of return on plan assets 0.00% 0.00% 0.00%
Discount rate [1] 5.50% 3.00% 2.80%
Other Postretirement Benefits [Member]      
Information about Plan Assets [Abstract]      
Pension contributions $ 104,000 $ 109,000  
Fair value of plan assets $ 0 $ 0 $ 0
Pension plan defined benefit plan cost increase limit percentage 4.00%    
Discount rate 5.50% 3.00% 2.80%
Seafarers Pension Trust [Member]      
Information about Plan Assets [Abstract]      
Pension contributions $ 400,000 $ 500,000  
Contribution percentage to defined contribution plan   100.00%  
Central Pension Fund of the International Union of Operating [Member]      
Information about Plan Assets [Abstract]      
Pension contributions 600,000 $ 700,000  
Contribution percentage to defined contribution plan   107.00%  
Higman Pension Plan [Member]      
Information about Plan Assets [Abstract]      
Pension contributions $ 8,200,000 $ 900,000 $ 500
Discount rate   3.10%  
[1] The 2023 discount rate for benefit cost is 5.5% for both the Kirby Pension Plan and the Higman Pension Plan. The 2022 discount rate for benefit cost is 3.0% for the Kirby Pension Plan and 3.1% for the Higman Pension Plan.