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Retirement Plans, Information About Plan Assets and Asset Allocation (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
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    
Level 3 [Member]      
Information about Plan Assets [Abstract]      
Fair value of plan assets $ 0 $ 0  
Cash and Equity Securities [Member] | Level 1 [Member]      
Information about Plan Assets [Abstract]      
Fair value of plan assets 4,800 5,400  
Higman [Member]      
Information about Plan Assets [Abstract]      
Pension contributions 900 500 $ 2,200
Pension Plan [Member]      
Information about Plan Assets [Abstract]      
Pension contributions 906 479  
Fair value of plan assets $ 341,061 $ 430,821 $ 395,137
Expected long-term rate of return on plan assets 6.75% 6.75% 6.75%
Contribution percentage to defined contribution plan 105.00%    
Discount rate 3.00% 2.80%  
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% 3.50%
Pension Plan [Member] | Maximum [Member]      
Information about Plan Assets [Abstract]      
Discount rate 3.10% [1] 2.90% 3.10%
Pension Plan [Member] | Higman [Member]      
Information about Plan Assets [Abstract]      
Discount rate 3.10% 2.90%  
Pension Plan [Member] | U.S. Equity Securities [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Asset allocations 50.00% 51.00%  
Target allocations 50.00%    
Pension Plan [Member] | U.S. Equity Securities [Member] | Minimum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Target allocations 45.00%    
Pension Plan [Member] | U.S. Equity Securities [Member] | Maximum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Target allocations 55.00%    
Pension Plan [Member] | International Equity Securities [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Asset allocations 20.00% 20.00%  
Target allocations 20.00%    
Pension Plan [Member] | International Equity Securities [Member] | Minimum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Target allocations 12.00%    
Pension Plan [Member] | International Equity Securities [Member] | Maximum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Target allocations 28.00%    
Pension Plan [Member] | Debt Securities [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Asset allocations 30.00% 29.00%  
Target allocations 30.00%    
Pension Plan [Member] | Debt Securities [Member] | Minimum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Target allocations 20.00%    
Pension Plan [Member] | Debt Securities [Member] | Maximum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Target allocations 40.00%    
Pension Plan [Member] | Cash and Cash Equivalents [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Asset allocations 0.00% 0.00%  
Target allocations 0.00%    
Pension Plan [Member] | Cash and Cash Equivalents [Member] | Minimum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Target allocations 0.00%    
Pension Plan [Member] | Cash and Cash Equivalents [Member] | Maximum [Member]      
Asset Allocation Among Asset Categories [Abstract]      
Target allocations 0.00%    
SERP [Member]      
Information about Plan Assets [Abstract]      
Pension contributions $ 155 $ 160  
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] 3.00% 2.80% 3.50%
Other Postretirement Benefits [Member]      
Information about Plan Assets [Abstract]      
Pension contributions $ 109 $ 168  
Fair value of plan assets $ 0 $ 0 $ 0
Pension plan defined benefit plan cost increase limit percentage 4.00%    
Discount rate 3.00% 2.80% 3.50%
Seafarers Pension Trust [Member]      
Information about Plan Assets [Abstract]      
Pension contributions $ 500 $ 500  
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 $ 700 $ 700  
Contribution percentage to defined contribution plan   103.00%  
[1] The 2022 discount rate for benefit cost is 3.0% for the Kirby Pension Plan and 3.1% for the Higman Pension Plan. The 2021 discount rate for benefit cost is 2.8% for the Kirby Pension Plan and 2.9% for the Higman Pension Plan.