EARNINGS PER SHARE (Computation of Basic and Diluted Earnings per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Basic
Net income per consolidated statements of income	$ 8,531	$ 6,291
Less: Earnings allocated to participating securities	(135)	(53)
Net income available to common stockholder	$ 8,396	$ 6,238
Weighted average common shares outstanding including participating securities	8,281,325	8,192,798
Less: Weighted average participating securities	(130,873)	(68,770)
Weighted average common shares outstanding	8,150,452	8,124,028
Basic earnings per common share (in dollars per share)	$ 1.03	$ 0.77
Diluted
Net income allocated to common shareholders	$ 8,396	$ 6,238
Weighted average common shares outstanding for basic earnings per common share	8,150,452	8,124,028
Average shares and dilutive potential common shares	8,285,220	8,275,243
Diluted earnings per common share (in dollars per share)	$ 1.01	$ 0.75
Stock Option
Diluted
Dilutive effects of assumed exercise of stock options/vesting of performance based restricted stock	114,740	151,215
Restricted stock
Diluted
Dilutive effects of assumed exercise of stock options/vesting of performance based restricted stock	20,028

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of undistributed earnings (loss) allocated to participating securities for the basic earnings (loss) per share or per unit calculation under the two-class method.

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