ALLOWANCE FOR CREDIT LOSSES (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 110,088	$ 131,606
Charge-offs	(13,217)	(2,126)
Recoveries	1,023	676
Provision (benefit)	2,628	16
Ending Balance	100,522	130,172
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	15,462	15,280
Provision (benefit)	617	(661)
Ending balance	16,079	14,619
Agricultural and Agricultural Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	5,213	7,129
Charge-offs	(3,104)	(318)
Recoveries	453	21
Provision (benefit)	105	279
Ending Balance	2,667	7,111
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	8,427	11,935
Charge-offs	(88)	(21)
Recoveries	0	5
Provision (benefit)	(464)	(907)
Ending Balance	7,875	11,012
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	9,050	12,770
Charge-offs	(5,396)	(798)
Recoveries	284	302
Provision (benefit)	4,857	(361)
Ending Balance	8,795	11,913
Commercial and Industrial \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	27,738	38,818
Charge-offs	(4,500)	(948)
Recoveries	206	293
Provision (benefit)	2,356	(2,068)
Ending Balance	25,800	36,095
Paycheck Protection Program ("PPP") \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	0	0
Charge-offs	0	0
Recoveries	0	0
Provision (benefit)	0	0
Ending Balance	0	0
Owner occupied commercial real estate \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	19,214	20,001
Charge-offs	0	(41)
Recoveries	40	53
Provision (benefit)	(1,279)	(597)
Ending Balance	17,975	19,416
Non-owner occupied commercial real estate \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	17,908	20,873
Charge-offs	(129)	0
Recoveries	33	0
Provision (benefit)	(1,799)	3,821
Ending Balance	16,013	24,694
Real Estate Construction \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	22,538	20,080
Charge-offs	0	0
Recoveries	7	2
Provision (benefit)	(1,148)	(151)
Ending Balance	$ 21,397	$ 19,931

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

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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