EARNINGS PER SHARE (Computation of Basic and Diluted Earnings per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Basic
Net income per consolidated statements of income	$ 16,215	$ 10,783	$ 41,668	$ 27,690
Less: Earnings allocated to participating securities	(508)	(89)	(568)	(255)
Net income available to common stockholders	$ 15,707	$ 10,694	$ 41,100	$ 27,435
Weighted average common shares outstanding including participating securities	8,897,910	8,291,068	8,518,639	8,296,701
Less: Weighted average participating securities	(278,937)	(68,198)	(116,045)	(76,499)
Weighted average common shares outstanding	8,618,973	8,222,870	8,402,594	8,220,202
Basic earnings per common share (in dollars per share)	$ 1.82	$ 1.30	$ 4.89	$ 3.34
Diluted
Net income allocated to common shareholders	$ 15,707	$ 10,694	$ 41,100	$ 27,435
Weighted average common shares outstanding for basic earnings per common share	8,618,973	8,222,870	8,402,594	8,220,202
Average shares and dilutive potential common shares	8,893,104	8,393,211	8,636,397	8,392,055
Diluted earnings per common share (in dollars per share)	$ 1.77	$ 1.27	$ 4.76	$ 3.27
Stock Option
Diluted
Add: Dilutive effects of assumed exercise of stock options	173,909	92,269	161,932	103,737
Performance-Based Restricted Stock Units (PRSUs)
Diluted
Dilutive effects of assumed vesting units	53,571	78,072	41,932	68,116
Restricted stock
Calculations of basic and diluted earnings per share
Number of antidilutive shares not considered in computing diluted earnings per share	188,906		188,906
Diluted
Dilutive effects of assumed vesting units	46,651		29,939