LOANS - Total Loans Outstanding (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Mar. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 4,492,257		$ 4,291,105
Percentage of loans receivable	100.00%	100.00%
Less: Allowance for credit losses		$ (67,239)	$ (67,523)	(67,773)	$ (73,048)	$ (71,713)	$ (61,408)
Net deferred loan fees		(2,422)		(3,264)
Loans, net		4,422,596		4,220,068
Total commercial loans | Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 4,010,960		3,863,630
Percentage of loans receivable	90.10%	89.20%
Total consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 481,297		427,475
Percentage of loans receivable	9.90%	10.80%
Other consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 93,026		82,755
Percentage of loans receivable	1.90%	2.10%
Commercial and industrial loans:
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 1,511,295		1,389,469
Percentage of loans receivable	32.40%	33.60%
Commercial and industrial loans: | Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Less: Allowance for credit losses		$ (32,348)	(31,195)	(30,595)	(36,676)	(33,130)	(28,333)
Commercial and industrial loans: | Working capital lines of credit loans | Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 684,281		652,861
Percentage of loans receivable	15.20%	15.20%
Commercial and industrial loans: | Non-working capital loans | Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 827,014		736,608
Percentage of loans receivable	17.20%	18.40%
Commercial real estate and multi-family residential loans:
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 2,056,768		1,954,846
Percentage of loans receivable	45.60%	45.80%
Commercial real estate and multi-family residential loans: | Construction and land development loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 468,288		379,813
Percentage of loans receivable	8.90%	10.40%
Commercial real estate and multi-family residential loans: | Owner occupied loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 741,293		739,371
Percentage of loans receivable	17.20%	16.50%
Commercial real estate and multi-family residential loans: | Nonowner occupied loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 655,975		588,458
Percentage of loans receivable	13.70%	14.60%
Commercial real estate and multi-family residential loans: | Multifamily loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 191,212		247,204
Percentage of loans receivable	5.80%	4.30%
Agri-business and agricultural loans:
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 342,066		445,825
Percentage of loans receivable	10.40%	7.60%
Agri-business and agricultural loans: | Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Less: Allowance for credit losses		$ (4,206)	$ (4,753)	(5,034)	$ (3,686)	$ (3,930)	$ (3,043)
Agri-business and agricultural loans: | Loans secured by farmland | Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 165,328		206,331
Percentage of loans receivable	4.80%	3.70%
Agri-business and agricultural loans: | Loans for agricultural production | Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 176,738		239,494
Percentage of loans receivable	5.60%	3.90%
Other commercial loans:
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 100,831		73,490
Percentage of loans receivable	1.70%	2.20%
Consumer 1-4 family mortgage loans:
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 388,271		344,720
Percentage of loans receivable	8.00%	8.70%
Consumer 1-4 family mortgage loans: | Closed end first mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 196,077		176,561
Percentage of loans receivable	4.10%	4.40%
Consumer 1-4 family mortgage loans: | Open end and junior lien loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 173,419		156,238
Percentage of loans receivable	3.60%	3.90%
Consumer 1-4 family mortgage loans: | Residential construction and land development loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable before allowance for credit loss		$ 18,775		$ 11,921
Percentage of loans receivable	0.30%	0.40%