PARENT COMPANY CONDENSED FINANCIAL INFORMATION - INCOME AND COMPREHENSIVE INCOME (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income and expenses:
Interest income	$ 51,379	$ 53,772	$ 51,552	$ 69,557	$ 57,970	$ 56,038	$ 57,091	$ 81,159	$ 226,260	$ 252,258	$ 280,883
Less: Interest expense	1,038	1,340	1,511	1,777	2,850	3,786	4,886	8,421	5,666	19,943	44,757
Less: Other expenses									13,024	15,614	15,416
INCOME BEFORE INCOME TAX EXPENSE	19,809	26,227	30,561	33,744	23,632	25,826	19,597	33,578	110,341	102,633	113,193
Income tax benefit	(3,004)	(6,218)	(6,639)	(7,691)	(3,276)	(5,437)	(3,793)	(6,881)	(23,552)	(19,387)	(21,494)
NET INCOME	$ 16,805	$ 20,009	$ 23,922	$ 26,053	$ 20,356	$ 20,389	$ 15,804	$ 26,697	86,789	83,246	91,699
COMPREHENSIVE INCOME									80,154	88,657	95,794
Parent
Income and expenses:
Dividends from subsidiary									28,300	25,980	24,249
Interest income									143	182	250
Other income									53	57	54
Less: Interest expense									507	1,000	1,620
Less: Other expenses									760	691	511
INCOME BEFORE INCOME TAX EXPENSE									27,229	24,528	22,422
Income tax benefit									245	344	1,213
Income before equity in undistributed net income of subsidiaries									27,474	24,872	23,635
Equity in undistributed net income of subsidiaries									59,315	58,374	68,064
NET INCOME									86,789	83,246	91,699
COMPREHENSIVE INCOME									$ 80,154	$ 88,657	$ 95,794