RETIREMENT PLANS, CHANGES IN PROJECTED BENEFIT OBLIGATION (Details) - Qualified noncontributory defined benefit retirement plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of changes in projected benefit obligation [Abstract]
Projected benefit obligation at beginning of year	$ 2,045	$ 1,900	$ 1,971
Service cost	0	0	0
Interest cost	63	77	69
Actuarial (gain) or loss	155	122	(86)
Benefits paid	(139)	(54)	(54)
Projected benefit obligation at end of year	$ 2,124	$ 2,045	$ 1,900