DEFERRED COMPENSATION PLANS - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Cash surrender value of life insurance	$ 176,500	$ 175,300
Deferred compensation arrangement with individual, recorded liability	722	698
Deferred compensation arrangement with individual, compensation expense	830	386	$ 739
Supplemental Employee Retirement Plan
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation arrangement with individual, recorded liability	$ 9,800	$ 9,500