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Retirement Plans, Weighted-Average Assumption Used to Determine Benefit Obligation (Details)
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Pension Plan [Member]    
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]    
Discount rate 5.50% [1] 3.00%
Health care cost trend rate [Abstract]    
Initial rate 0.00% 0.00%
Ultimate rate 0.00% 0.00%
Pension Plan [Member] | Minimum [Member]    
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]    
Discount rate [1]   3.00%
Pension Plan [Member] | Maximum [Member]    
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]    
Discount rate [1]   3.10%
Pension Plan [Member] | Higman [Member]    
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]    
Discount rate 5.50% 3.10%
SERP [Member]    
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]    
Discount rate [1] 5.50% 3.00%
Rate of compensation increase 0.00% 0.00%
Health care cost trend rate [Abstract]    
Initial rate 0.00% 0.00%
Ultimate rate 0.00% 0.00%
Other Postretirement Benefits [Member]    
Weighted-average assumption used to determine benefit obligation at end of year [Abstract]    
Discount rate [1] 5.50% 3.00%
Rate of compensation increase 0.00% 0.00%
Health care cost trend rate [Abstract]    
Initial rate 6.50% 6.25%
Ultimate rate 5.00% 5.00%
Years to ultimate 2029 2027
[1] The 2022 discount rate was 5.5% for both the Kirby Pension Plan and the Higman Pension Plan. The 2021 discount rate was 3.0% for the Kirby Pension Plan and 3.1% for the Higman Pension Plan.