ALLOWANCE FOR LOAN LOSSES (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	$ 61,963	$ 55,686
Charge-offs	(1,950)	(2,224)
Recoveries	991	931
Provision	1,635	4,263
Ending Balance	62,639	58,656
Agricultural and Agricultural Real Estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	4,953	4,258
Charge-offs	(379)	0
Recoveries	330	14
Provision	694	444
Ending Balance	5,598	4,716
Residential Real Estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	1,785	2,224
Charge-offs	(163)	(16)
Recoveries	13	75
Provision	(30)	(142)
Ending Balance	1,605	2,141
Consumer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	5,182	9,156
Charge-offs	(725)	(1,289)
Recoveries	322	290
Provision	49	778
Ending Balance	4,828	8,935
Commercial \| Commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	24,505	18,098
Charge-offs	(644)	(794)
Recoveries	175	104
Provision	(215)	1,987
Ending Balance	23,821	19,395
Commercial Real Estate \| Commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	25,538	21,950
Charge-offs	(39)	(125)
Recoveries	151	448
Provision	1,137	1,196
Ending Balance	$ 26,787	$ 23,469

A valuation allowance for financing receivables that are expected to be uncollectible.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of direct write-downs of financing receivables charged against the allowance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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