RETIREMENT AND POSTRETIREMENT PLANS - Employee Retirement Plans investments measured at fair value (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
BNB Bank Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	$ 38,572	$ 47,857
Expected annual rates of return	7.25%	7.25%
Percentage of investments for long term growth.	97.00%
Percentage of near term benefit payments	3.00%
Percentage of cumulative long term return on index	9.00%
Percentage of cumulative long term return on bonds	5.00%
Employee Retirement Plan's target allocation, expected annual rate of return	7.25%
Actuarial (gain) loss	$ (7,111)	$ (304)
BNB Bank Pension Plan | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	1,001	1,581
BNB Bank Pension Plan | U.S. large cap
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	14,310	13,623
BNB Bank Pension Plan | U.S. mid cap/small cap
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	4,094	5,669
BNB Bank Pension Plan | International
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	4,658	8,332
BNB Bank Pension Plan | Equities blend
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	308	900
BNB Bank Pension Plan | Corporate
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	2,203	1,696
BNB Bank Pension Plan | Government
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	4,275	1,700
BNB Bank Pension Plan | Mortgage-backed
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	979	2,549
BNB Bank Pension Plan | High yield bonds and bond funds
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	6,744	11,807
BNB Bank Pension Plan | Domestic Mid Cap.
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets		47,857
BNB Bank Pension Plan | Level 1 Inputs
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	27,645
BNB Bank Pension Plan | Level 1 Inputs | U.S. large cap
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	14,310	13,623
BNB Bank Pension Plan | Level 1 Inputs | U.S. mid cap/small cap
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	4,094	5,669
BNB Bank Pension Plan | Level 1 Inputs | International
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	4,658	8,332
BNB Bank Pension Plan | Level 1 Inputs | Equities blend
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	308	900
BNB Bank Pension Plan | Level 1 Inputs | Government
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	4,275	1,700
BNB Bank Pension Plan | Level 1 Inputs | Domestic Mid Cap.
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets		30,224
BNB Bank Pension Plan | Level 2 Inputs
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	10,927
BNB Bank Pension Plan | Level 2 Inputs | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	1,001	1,581
BNB Bank Pension Plan | Level 2 Inputs | Corporate
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	2,203	1,696
BNB Bank Pension Plan | Level 2 Inputs | Mortgage-backed
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	979	2,549
BNB Bank Pension Plan | Level 2 Inputs | High yield bonds and bond funds
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	6,744	11,807
BNB Bank Pension Plan | Level 2 Inputs | Domestic Mid Cap.
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets		17,633
Employee Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	$ 22,593	$ 28,693	$ 27,142
Expected annual rates of return	7.00%	7.00%	7.00%
Percentage of investments for long term growth.	97.00%
Percentage of near term benefit payments	3.00%
Percentage of cumulative long term return on index	9.00%
Percentage of cumulative long term return on bonds	5.00%
Employee Retirement Plan's target allocation, expected annual rate of return	7.00%	7.00%
Actuarial (gain) loss	$ (5,004)	$ (903)
Employee Retirement Plan | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	541	1,001
Employee Retirement Plan | U.S. large cap
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	8,398	8,579
Employee Retirement Plan | U.S. mid cap/small cap
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	2,348	2,896
Employee Retirement Plan | International
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	2,718	3,560
Employee Retirement Plan | Equities blend
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	192	479
Employee Retirement Plan | Corporate
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	1,305	1,288
Employee Retirement Plan | Government
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	2,527	1,406
Employee Retirement Plan | Mortgage-backed
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	586	1,858
Employee Retirement Plan | High yield bonds and bond funds
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	3,978	7,626
Employee Retirement Plan | Domestic Mid Cap.
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	22,593	28,693
Employee Retirement Plan | Level 1 Inputs | U.S. large cap
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	8,398	8,579
Employee Retirement Plan | Level 1 Inputs | U.S. mid cap/small cap
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	2,348	2,896
Employee Retirement Plan | Level 1 Inputs | International
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	2,718	3,560
Employee Retirement Plan | Level 1 Inputs | Equities blend
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	192	479
Employee Retirement Plan | Level 1 Inputs | Government
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	2,527	1,406
Employee Retirement Plan | Level 1 Inputs | Domestic Mid Cap.
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	16,183	16,920
Employee Retirement Plan | Level 2 Inputs | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	541	1,001
Employee Retirement Plan | Level 2 Inputs | Corporate
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	1,305	1,288
Employee Retirement Plan | Level 2 Inputs | Mortgage-backed
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	586	1,858
Employee Retirement Plan | Level 2 Inputs | High yield bonds and bond funds
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	3,978	7,626
Employee Retirement Plan | Level 2 Inputs | Domestic Mid Cap.
Defined Benefit Plan Disclosure [Line Items]
Total Plan Assets	$ 6,410	$ 11,773