FAIR VALUE (Quantitative Information about Level 3 fair value measurements) (Details) - Level 3 $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	$ 0	$ 0
Interest rate lock commitments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	1,425	1,827
Discounted cash flows
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing rights	5,559	5,189
Modified appraised value
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other real estate owned	6,314	6,624
Modified appraised value \| Agricultural and agricultural real estate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Collateral dependent impaired loans	14,161	12,451
Modified appraised value \| Premises, furniture and equipment held for sale
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Premises, furniture and equipment held for sale	6,925	6,499
Interest rate lock commitments \| Discounted cash flows
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets	$ 1,425	$ 1,827
Closing ratio \| Discounted cash flows \| Weighted Average \| Interest rate lock commitments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	0.88	0.86
Closing ratio \| Discounted cash flows \| Minimum \| Interest rate lock commitments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	0	0
Closing ratio \| Discounted cash flows \| Maximum \| Interest rate lock commitments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	0.99	0.99
Appraisal discount \| Modified appraised value \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	0.00%	0.00%
Appraisal discount \| Modified appraised value \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	10.00%	10.00%
Appraisal discount \| Modified appraised value \| Premises, furniture and equipment held for sale \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	0.00%	0.00%
Appraisal discount \| Modified appraised value \| Premises, furniture and equipment held for sale \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	10.00%	10.00%
Commercial and industrial \| Modified appraised value \| Commercial and industrial
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Collateral dependent impaired loans	$ 8,969	$ 11,256
Commercial and industrial \| Modified appraised value \| Owner occupied commercial real estate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Collateral dependent impaired loans	3,573	5,874
Commercial and industrial \| Modified appraised value \| Non-owner occupied commercial real estate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Collateral dependent impaired loans	$ 14,742	$ 4,907
Commercial and industrial \| Appraisal discount \| Modified appraised value \| Commercial and industrial \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	0.00%	0.00%
Commercial and industrial \| Appraisal discount \| Modified appraised value \| Commercial and industrial \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	8.00%	8.00%
Commercial and industrial \| Appraisal discount \| Modified appraised value \| Owner occupied commercial real estate \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	0.00%	0.00%
Commercial and industrial \| Appraisal discount \| Modified appraised value \| Owner occupied commercial real estate \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	7.00%	12.00%
Commercial and industrial \| Appraisal discount \| Modified appraised value \| Non-owner occupied commercial real estate \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	0.00%	0.00%
Commercial and industrial \| Appraisal discount \| Modified appraised value \| Non-owner occupied commercial real estate \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	10.00%	10.00%
Agricultural and agricultural real estate \| Appraisal discount \| Modified appraised value \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	0.00%	0.00%
Agricultural and agricultural real estate \| Appraisal discount \| Modified appraised value \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Servicing assets, discount rate	15.00%	10.00%

Collateral Dependent Impaired Loans

No definition available.

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- Definition

Other Real Estate, Fair Value Disclosure

+ References

No definition available.

+ Details

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- Definition

Amount of assets held-for-sale that are not part of a disposal group.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 15
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=121558832&loc=d3e400-110220

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- Definition

Value of input used to measure derivative asset.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ References

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