EMPLOYEE BENEFITS - Schedule of Shares Issued in Connection with Stock Compensation Awards (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from stock options exercised	$ 1,692	$ 1,986	$ 2,653
Stock options \| Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from stock options exercised	1,692	1,986	2,653
Total intrinsic value of stock options exercised during period	$ 881	$ 1,106	$ 1,384
New shares issued from available treasury shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
New shares issued (in shares)	116,661	122,537	140,692

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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Number of shares issued under share-based payment arrangement.

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