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EMPLOYEE RETIREMENT PLANS - Additional Information (Details)
12 Months Ended
Dec. 31, 2020
USD ($)
participant
multiple
denominator
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Dec. 31, 2021
USD ($)
Defined Benefit Plan Disclosure [Line Items]        
Maximum contribution percentage (in hundredths) 90.00%      
Matching contribution limit (in hundredths) 3.00%      
Contributions to the 401(k) Plan $ 1,100,000 $ 880,000 $ 1,200,000  
Prior service cost expected to be amortized in next fiscal year $ 1,099,000      
Supplemental Executive Retirement Plan [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Number of participants | participant 7      
Factor used to determine annual base salary | multiple 12      
Annual base salary period (in months) 24 months      
Age of participant (in years) 65 years      
Minimum period of service (in years) 20 years      
Benefit percentage, tier one (in hundredths) 50.00%      
Benefit percentage, tier two (in hundredths) 25.00%      
Benefit percentage, tier three (in hundredths) 15.00%      
Minimum period of service for prorated benefit (in years) 15 years      
Factor used to determine prorated benefit | denominator 20      
Installment period (in years) 10 years      
Benefit percentage for special participants (in hundredths) 50.00%      
Initial prior service cost for retirement plan $ 43,400,000      
Accumulated benefit obligation $ 74,200,000 $ 48,100,000    
Defined benefit plan threshold of benefit obligation at which actuarial losses are amortized (in hundredths) 10.00%      
Supplemental Executive Retirement Plan [Member] | Forecast [Member]        
Defined Benefit Plan Disclosure [Line Items]        
Prior service cost expected to be amortized in next fiscal year       $ 6,000,000.0