EMPLOYEE BENEFITS - Narrative (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Employee stock ownership plan, maximum employer contribution as a percentage of participant's qualified compensation	5.00%
Employee stock ownership plan, total contributions accrued or paid	$ 1,031	$ 973
Employee stock ownership plan, shares held under plan (in shares)	1,253,010		1,224,697
Employee stock ownership plan, unallocated shares (in shares)	0		0
Cash surrender value of life insurance	$ 35,304		$ 34,495
Bonus expense	1,610	2,304
Executive Incentive Retirement Plan | Postretirement Life Insurance | Nonqualified Plan | Unfunded Plan
Defined Benefit Plan Disclosure [Line Items]
Cash surrender value of life insurance	35,304		34,495
Plan cost	500	$ 504	602
Plan obligation	$ 4,424		$ 4,081