ALLOWANCE FOR CREDIT LOSSES (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 131,606	$ 70,395
Charge-offs	(2,126)	(6,300)
Recoveries	676	1,319
Provision	16	19,865
Ending Balance	130,172	97,350
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	15,280	248
Impact of ASU 2016-13 adoption on January 1, 2020	14,619	15,468
Provision	(661)	1,616
Ending balance	14,619	15,468
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		12,071
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance		13,604
Impact of ASU 2016-13 adoption on January 1, 2020		13,604
Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		82,466
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance		13,852
Impact of ASU 2016-13 adoption on January 1, 2020		13,852
Agricultural and Agricultural Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	7,129	5,680
Charge-offs	(318)	(253)
Recoveries	21	826
Provision	279	(1,069)
Ending Balance	7,111	4,797
Agricultural and Agricultural Real Estate \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		(387)
Agricultural and Agricultural Real Estate \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		5,293
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	11,935	1,504
Charge-offs	(21)	(79)
Recoveries	5	3
Provision	(907)	2,480
Ending Balance	11,012	8,725
Residential Real Estate \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		4,817
Residential Real Estate \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		6,321
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	12,770	4,822
Charge-offs	(798)	(717)
Recoveries	302	220
Provision	(361)	1,131
Ending Balance	11,913	9,765
Consumer \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		4,309
Consumer \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		9,131
Commercial and Industrial \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	38,818	34,207
Charge-offs	(948)	(5,230)
Recoveries	293	264
Provision	(2,068)	3,486
Ending Balance	36,095	32,455
Commercial and Industrial \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		(272)
Commercial and Industrial \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		33,935
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	0	0
Ending Balance	0	0
Paycheck Protection Program ("PPP") \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		0
Paycheck Protection Program ("PPP") \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		0
Owner occupied commercial real estate \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	20,001	7,921
Charge-offs	(41)
Recoveries	53	1
Provision	(597)	2,529
Ending Balance	19,416	10,337
Owner occupied commercial real estate \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		(114)
Owner occupied commercial real estate \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		7,807
Non-owner occupied commercial real estate \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	20,873	7,584
Charge-offs	0	0
Recoveries	0	0
Provision	3,821	3,353
Ending Balance	24,694	8,320
Non-owner occupied commercial real estate \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		(2,617)
Non-owner occupied commercial real estate \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		4,967
Real Estate Construction \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	20,080	8,677
Charge-offs	0	(21)
Recoveries	2	5
Provision	(151)	7,955
Ending Balance	$ 19,931	22,951
Real Estate Construction \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		6,335
Real Estate Construction \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance		$ 15,012

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 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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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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