EMPLOYEE BENEFIT PLAN - SERP (Details) - USD ($)	1 Months Ended	3 Months Ended			9 Months Ended
	Oct. 31, 2020	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Employer contribution					$ 0	$ 0
Settlement loss			$ (4,700,000)
Unrealized gain/loss due to change in fair value of SERP liabilities		$ (152,000)		$ (186,000)	(458,000)	(1,104,000)
Non-qualified Supplemental Retirement Plan ("SERP")
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		31,600,000	32,000,000.0		31,600,000
Trading gains (losses), net		407,000		1,100,000	2,500,000	178,000
SERP Liabilities		29,300,000	$ 29,700,000		29,300,000
Unrealized gain/loss due to change in fair value of SERP liabilities		$ 502,000		$ 1,200,000	$ 2,800,000	$ (486,000)
Retirement Income Plan
Defined Benefit Plan Disclosure [Line Items]
Vested balance age	59 years 6 months