EMPLOYEE BENEFIT PLANS, Noncontributory Defined Benefit Pension Plan (Details)	12 Months Ended
	Dec. 31, 2020 USD ($) Plan	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
EMPLOYEE BENEFIT PLANS [Abstract]
Number of plans | Plan	2
Employer discretionary contribution to 401 (k) plan	$ 212,000	$ 200,000	$ 151,000
Amounts recognized in accumulated other comprehensive loss consists of [Abstract]
Total	(543,000)	29,000	181,000
Pension Plan [Member]
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of year	13,027,000	17,895,000
Service cost	330,000	289,000	359,000
Interest cost	332,000	588,000	652,000
Actuarial (Gain) / Loss	1,810,000	1,706,000
Settlement gain	(34,000)	(259,000)
Benefits paid	(1,445,000)	(7,192,000)
Benefit obligation at end of year	14,020,000	13,027,000	17,895,000
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of year	13,277,000	18,212,000
Actual return (loss) on plan assets	1,415,000	2,394,000
Employer contributions	0	0
Plan expenses	0	(37,000)
Transfer to 401(k) plan	0	(100,000)
Benefits paid	(1,445,000)	(7,192,000)
Fair value of plan assets at end of year	13,247,000	13,277,000	18,212,000
Funded status	(773,000)	250,000
Amounts recognized in accumulated other comprehensive loss consists of [Abstract]
Net loss	4,383,000	3,727,000
Prior service cost	0	(32,000)
Total	4,383,000	3,695,000
Components of net periodic benefit cost [Abstract]
Service cost	330,000	289,000	359,000
Interest cost	332,000	588,000	652,000
Return on plan assets	(862,000)	(924,000)	(1,126,000)
Settlement loss (gain)	302,000	(259,000)	0
Net amortization and deferral	233,000	272,000	186,000
Net periodic benefit cost	335,000	$ (34,000)	$ 71,000
Amounts that will be amortized from accumulated other comprehensive loss into the net periodic benefit cost in 2021, related to estimated net loss	$ 364,000
Weighted-average assumptions used to determine benefit obligations [Abstract]
Rate of compensation increase	3.00%	3.00%
Weighted-average assumptions used to determine net periodic benefit cost (income) [Abstract]
Rate of compensation increase	3.00%	3.00%	3.00%
Pension Plan [Member] | FCCB Plan [Member]
Weighted-average assumptions used to determine benefit obligations [Abstract]
Discount rate	2.00%	2.75%
Weighted-average assumptions used to determine net periodic benefit cost (income) [Abstract]
Discount rate	2.75%	4.00%	3.35%
Expected long-term return on plan assets	7.00%	7.00%	7.00%
Pension Plan [Member] | FNB Plan [Member]
Weighted-average assumptions used to determine benefit obligations [Abstract]
Discount rate	0.00%	3.33%
Weighted-average assumptions used to determine net periodic benefit cost (income) [Abstract]
Discount rate		3.49%	3.35%
Expected long-term return on plan assets			3.00%