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EMPLOYEE BENEFIT PLANS - Narrative (Details) - USD ($)
12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Employee benefit plans      
Maximum participants' contribution as a percentage of pre-tax compensation 50.00%    
Employer matching contribution and percent of match 75.00%    
Company contributions $ 8,200,000 $ 7,100,000 $ 7,400,000
Recorded value of noncurrent investments $ 66,700,000 59,000,000  
Other postretirement plan Other Postretirement PlanThe Company provides substantially all active, permanent employees with medical, dental, and vision benefits through a self-insured plan. Employees retiring at or after age 58, along with their spouses and dependents, continue participation in the plan by payment of a premium. Plan assets are invested in mutual funds, short-term money market instruments and commercial paper based upon a similar asset mix to the pension plan. Retired employees are also provided with a $10,000 dollar life insurance benefit.The Company records the costs of postretirement benefits other than pensions (PBOP) during the employees' years of active service. In 2023, the Company recorded postretirement benefit income of $2.9 million. In 2022 and 2021, postretirement benefit expense was recorded for $0.1 million and $0.2 million, respectively.    
Annual rate of increase in the per capita cost 6.20%    
Health care cost trend rate assumed, year three 6.00%    
Health care cost trend rate, net periodic benefit cost 4.00%    
Domestic Equity: Large Cap Stocks      
Employee benefit plans      
Index percentage 35.00%    
Domestic Equity: Small/Mid Cap Stocks      
Employee benefit plans      
Index percentage 15.00%    
Non U.S. Equities      
Employee benefit plans      
Index percentage 10.00%    
Long-term rate of return on plan assets 9.00%    
Fixed Income Securities      
Employee benefit plans      
Index percentage 40.00%    
Fixed Income      
Employee benefit plans      
Assumed percentage of portfolio investment 40.00%    
Assumed long-term inflation rate 2.23%    
Equity Securities      
Employee benefit plans      
Assumed percentage of portfolio investment 60.00%    
Assumed long-term inflation rate 2.23%    
Minimum | Fixed Income      
Employee benefit plans      
Maturity period 1 year    
Maximum      
Employee benefit plans      
Employer matching contribution and percent of match 6.00%    
Maximum | Fixed Income      
Employee benefit plans      
Maturity period 5 years    
Pension Benefits      
Employee benefit plans      
Accumulated benefit obligations $ 534,700,000 505,900,000  
Fair value of pension plan assets 716,273,000 637,330,000 810,469,000
Net periodic (income) cost $ (378,000) $ 20,996,000 27,253,000
Long-term rate of return on plan assets 7.56% 7.50%  
Estimated annual contributions in next fiscal year $ 700,000    
Pension Benefits | Fixed Income      
Employee benefit plans      
Assumed returns 5.43%    
Pension Benefits | Money Market Fund Investments | Level 1      
Employee benefit plans      
Fair value of pension plan assets $ 400,000 $ 600,000  
Pension Benefits | Total Domestic Equity:      
Employee benefit plans      
Assumed long-term inflation rate 8.41%    
SERP      
Employee benefit plans      
Accumulated benefit obligations $ 74,100,000 69,300,000  
Other Benefits      
Employee benefit plans      
Fair value of pension plan assets 163,367,000 144,686,000 169,436,000
Life insurance benefit 10,000    
Net periodic (income) cost $ (2,854,000) $ 88,000 $ 227,000
Long-term rate of return on plan assets 7.41% 7.36%  
Estimated annual contributions in next fiscal year $ 200,000    
Other Benefits | Money Market Fund Investments | Level 1      
Employee benefit plans      
Fair value of pension plan assets $ 300,000 $ 0  
Other Benefits | Short-term cash investments      
Employee benefit plans      
Assumed returns 5.15%