ALLOWANCE FOR CREDIT LOSSES (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 119,937	$ 63,850	$ 70,395	$ 61,963
Charge-offs	(21,753)	(4,842)	(31,618)	(11,572)
Recoveries	452	2,013	2,916	4,077
Provision	4,741	5,201	49,613	11,754
Ending Balance	103,377	66,222	103,377	66,222
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning balance	17,392		248
Impact of ASU 2016-13 adoption on January 1, 2020	14,330		14,330
Provision	(3,062)		478
Ending balance	14,330		14,330
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	5,701	5,986	5,673	4,914
Charge-offs	(936)	(1,673)	(1,190)	(2,100)
Recoveries	0	199	826	528
Provision	576	858	412	2,028
Ending Balance	5,341	5,370	5,341	5,370
Agricultural and Agricultural Real Estate \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance			(380)
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	9,304	1,592	1,504	1,813
Charge-offs	(54)	(3)	(368)	(344)
Recoveries	2	52	97	138
Provision	419	164	3,621	198
Ending Balance	9,671	1,805	9,671	1,805
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	10,170	4,918	4,816	5,296
Charge-offs	(332)	(446)	(929)	(1,266)
Recoveries	69	95	413	839
Provision	(283)	371	1,009	69
Ending Balance	9,624	4,938	9,624	4,938
Consumer \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance			4,315
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	32,531	27,680	30,787	26,306
Charge-offs	(7,077)	(2,656)	(15,440)	(7,607)
Recoveries	369	1,526	1,153	2,110
Provision	8,775	1,874	14,951	7,615
Ending Balance	34,598	28,424	34,598	28,424
Commercial and Industrial \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance			3,147
Commercial and Industrial \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjusted Balance
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance			33,934
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	23,402	6,182	8,214	6,525
Charge-offs	(13,328)	(43)	(13,541)	(79)
Recoveries	0	3	192	96
Provision	1,155	1,108	16,771	708
Ending Balance	11,229	7,250	11,229	7,250
Owner occupied commercial real estate \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance			(407)
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	10,162	7,482	7,802	7,430
Charge-offs	(26)	(21)	(45)	(21)
Recoveries	10	100	18	200
Provision	1,981	186	7,186	138
Ending Balance	12,127	7,747	12,127	7,747
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			(2,834)
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			4,968
Real Estate Construction \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	28,667	10,010	11,599	9,679
Charge-offs	0	0	(105)	(155)
Recoveries	2	38	217	166
Provision	(7,882)	640	5,663	998
Ending Balance	$ 20,787	$ 10,688	20,787	$ 10,688
Real Estate Construction \| Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance			3,413
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 increase in allowance for credit loss on financing receivable from recovery.

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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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