OTHER BENEFIT PLANS (Additional Information) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of Other Benefit Plan [Line Items]
Potential Cash Payments Under Employment Agreements	$ 5,200,000
Directors' Deferred Compensation and Cash Plans [Member]
Summary of Other Benefit Plan [Line Items]
Deferred Compensation Liability	4,800,000	$ 4,400,000
Deferred Compensation Arrangement with Individual, Compensation Expense	505,000	515,000	$ 486,000
Other Employee Benefit Plans [Member]
Summary of Other Benefit Plan [Line Items]
Deferred Compensation Expense	1,000,000.0	461,000	(31,000)
Deferred Compensation Liability	5,700,000	4,200,000
Retirement Benefits Plan 401k [Member]
Summary of Other Benefit Plan [Line Items]
Deferred Compensation Expense	$ 1,900,000	$ 1,800,000	$ 1,800,000
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	6.00%