EARNINGS PER COMMON SHARE - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Basic earnings per common share computation:
Net income per condensed consolidated statements of income	$ 14,363	$ 12,915	$ 28,533	$ 26,021
Net earnings allocated to participating securities	(68)	(47)	(132)	(92)
Net earnings allocated to common stock	$ 14,295	$ 12,868	$ 28,401	$ 25,929
Weighted average common shares outstanding, including shares considered participating securities (in shares)	16,860	16,885	16,871	16,870
Less: Average participating securities (in shares)	(78)	(60)	(75)	(58)
Weighted average shares (in shares)	16,782	16,825	16,796	16,812
Basic earnings per common share (in dollar per share)	$ 0.85	$ 0.76	$ 1.69	$ 1.54
Diluted earnings per common share computation:
Net earnings allocated to common stock	$ 14,295	$ 12,868	$ 28,401	$ 25,929
Weighted average common shares outstanding for basic earnings per common share (in shares)	16,782	16,825	16,796	16,812
Add: Dilutive effects of performance based-shares (in shares)	33	0	33	0
Weighted average shares and dilutive potential common shares (in shares)	16,815	16,825	16,829	16,812
Diluted earnings per common share (in dollar per share)	$ 0.85	$ 0.76	$ 1.69	$ 1.54
Distributed earnings allocated to common stock
Basic earnings per common share computation:
Net earnings allocated to common stock	$ 2,935	$ 2,859	$ 5,879	$ 5,718
Undistributed earnings allocated to common stock
Basic earnings per common share computation:
Net earnings allocated to common stock	$ 11,360	$ 10,009	$ 22,522	$ 20,211