EMPLOYEE AND DIRECTOR BENEFIT PLANS - Additional information (Details)	12 Months Ended
Dec. 31, 2019 USD ($) item shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($)
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 460,000	$ 642,000	$ 768,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	6 years 6 months 26 days	4 years 10 months 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	6 years 6 months 26 days	4 years 9 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 740,000	$ 900,000,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	548,000	641,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	148,000	213,000	197,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 179,000	181,000	66,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 7 months 13 days
Deferred Compensation Liability, Current	$ 2,800,000	2,600,000
Proceeds from Stock Options Exercised	$ 228,000	$ 187,000	166,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number \| shares	268,542	239,955
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant \| shares	568,913	597,500
Number of stock grants awarded to independent directors \| shares	10,569.00
Value of stock grants awarded to independent directors	$ 130,000.00
Number of shares, that each director will receive \| shares	813.00
Deferred Profit Sharing [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Allocated Share-based Compensation Expense	$ 698,000	$ 639,000	465,000
Nonqualified Supplemental Executive Retirement Plan [Member] \| Chief Executive Officer [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Defined Benefit Plan Provisions	81,000	36,000	53,000
Liability, Defined Benefit Pension Plan	$ 24,000	85,000
Nonqualified Supplemental Executive Retirement Plan [Member] \| Executives [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of executives for whom supplemental executive retirement plan was approved \| item	2
Defined Benefit Plan Provisions	$ 64,000
Liability, Defined Benefit Pension Plan	64,000
Other Postretirement Benefit Plans, Defined Benefit1 [Member] \| Chief Executive Officer [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Defined Benefit Plan Provisions	81,000	(35,000)	36,000
Liability, Defined Benefit Pension Plan	265,000	286,000
Deferral Plan [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Allocated Share-based Compensation Expense	$ 200,000	$ 97,000	$ 178,000
2004 Omnibus Plan [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number \| shares	13,000
2008 Omnibus Plan [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number \| shares	33,200
2010 Omnibus Plan [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number \| shares	163,700
2018 Omnibus Plan [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number \| shares	58,500
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant \| shares	568,900

Amount of plan expenses provision deducted from total plan liabilities.

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Number of employees eligible for the defined benefit plan.

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Number of shares that each director will receive from the stock grants awarded by the company, during the period.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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Amount of liability, recognized in statement of financial position, for defined benefit pension plan. Excludes other postretirement benefit plan.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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