EARNINGS PER SHARE - Schedule of Earnings Per Share, Basic and Diluted (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
EARNINGS PER SHARE
Average common shares outstanding	12,581	13,710	12,775	13,713
Net income and net income available to common stockholders	$ 18,224	$ 20,114	$ 35,211	$ 38,982
Per common share amount	$ 1.45	$ 1.47	$ 2.76	$ 2.84
Average common shares outstanding	12,581	13,710	12,775	13,713
Net effect of dilutive stock options - based on the treasury stock method using average market price	102	102	108	94
Diluted common shares	12,683	13,812	12,883	13,807
Net income and net income available to common stockholders	$ 18,224	$ 20,114	$ 35,211	$ 38,982
Per common share amount	$ 1.44	$ 1.46	$ 2.73	$ 2.82