LOANS (Allowance for credit losses on financing receivables) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Credit Losses	$ 11,897	$ 9,426
Collectively Evaluated for Credit Losses	118,275	122,180
Total	130,172	131,606	$ 97,350	$ 70,395
Loans Individually Evaluated for Credit Losses	62,990	57,230
Loans Collectively Evaluated for Credit Losses	9,987,466	9,965,821
Total	10,050,456	10,023,051
Commercial and industrial \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Credit Losses	3,433	4,077
Collectively Evaluated for Credit Losses	32,662	34,741
Total	36,095	38,818	32,455	34,207
Loans Individually Evaluated for Credit Losses	14,560	16,578
Loans Collectively Evaluated for Credit Losses	2,406,700	2,518,221
Total	2,421,260	2,534,799
Commercial and industrial \| Paycheck Protection Program ("PPP")
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Credit Losses	0	0
Collectively Evaluated for Credit Losses	0	0
Total	0	0	0	0
Loans Individually Evaluated for Credit Losses	0	0
Loans Collectively Evaluated for Credit Losses	1,155,328	957,785
Total	1,155,328	957,785
Commercial and industrial \| Owner occupied commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Credit Losses	110	111
Collectively Evaluated for Credit Losses	19,306	19,890
Total	19,416	20,001	10,337	7,921
Loans Individually Evaluated for Credit Losses	10,720	11,174
Loans Collectively Evaluated for Credit Losses	1,826,839	1,765,232
Total	1,837,559	1,776,406
Commercial and industrial \| Non-owner occupied commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Credit Losses	5,873	3,250
Collectively Evaluated for Credit Losses	18,821	17,623
Total	24,694	20,873	8,320	7,584
Loans Individually Evaluated for Credit Losses	22,655	13,490
Loans Collectively Evaluated for Credit Losses	1,944,528	1,907,991
Total	1,967,183	1,921,481
Commercial and industrial \| Real estate construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Credit Losses	0	0
Collectively Evaluated for Credit Losses	19,931	20,080
Total	19,931	20,080	22,951	8,677
Loans Individually Evaluated for Credit Losses	0	0
Loans Collectively Evaluated for Credit Losses	796,027	863,220
Total	796,027	863,220
Agricultural and agricultural real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Credit Losses	2,481	1,988
Collectively Evaluated for Credit Losses	4,630	5,141
Total	7,111	7,129	4,797	5,680
Loans Individually Evaluated for Credit Losses	14,926	15,453
Loans Collectively Evaluated for Credit Losses	669,043	699,073
Total	683,969	714,526
Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Credit Losses	0	0
Collectively Evaluated for Credit Losses	11,012	11,935
Total	11,012	11,935	8,725	1,504
Loans Individually Evaluated for Credit Losses	129	535
Loans Collectively Evaluated for Credit Losses	786,865	839,907
Total	786,994	840,442
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Credit Losses	0	0
Collectively Evaluated for Credit Losses	11,913	12,770
Total	11,913	12,770	$ 9,765	$ 4,822
Loans Individually Evaluated for Credit Losses	0	0
Loans Collectively Evaluated for Credit Losses	402,136	414,392
Total	$ 402,136	$ 414,392

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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