FAIR VALUE MEASUREMENTS - QUANTITATIVE INFORMATION (Details) $ in Thousands	Sep. 30, 2019 USD ($) item	Dec. 31, 2018 USD ($) item
Fair Value Measurements
Mortgage servicing rights	$ 1,410	$ 1,536
Non-recurring
Fair Value Measurements
Impaired loans, at fair value	993	993
Other real estate owned	479	246
Non-recurring \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned	902
Mortgage servicing rights		430
Non-recurring \| Discounted cash flow \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Mortgage servicing rights	902	430
Non-recurring \| 1-4 family residential \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Impaired loans, at fair value		993
Other real estate owned	993
Non-recurring \| 1-4 family residential \| Sales comparison \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Impaired loans, at fair value	993	993
Non-recurring \| Agricultural \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned	233
Non-recurring \| Agricultural \| Sales comparison \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned	233
Non-recurring \| Commercial \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned	246	246
Non-recurring \| Commercial \| Income approach \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned	$ 246	$ 246
Non-recurring \| Minimum \| Discounted cash flow \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Servicing asset, measurement input	(0.08)	0.07
Non-recurring \| Minimum \| 1-4 family residential \| Sales comparison \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Impaired loans - measurement input	(0.30)	(0.21)
Non-recurring \| Minimum \| Agricultural \| Sales comparison \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned, measurement input	(0.29)
Non-recurring \| Minimum \| Commercial \| Income approach \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned, measurement input	0.1	0.10
Non-recurring \| Maximum \| Discounted cash flow \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Servicing asset, measurement input \| item		0.25
Non-recurring \| Maximum \| 1-4 family residential \| Sales comparison \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Impaired loans - measurement input	0.10	0.07
Non-recurring \| Maximum \| Agricultural \| Sales comparison \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned, measurement input	0.41
Non-recurring \| Maximum \| Residential \| Sales comparison \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Servicing asset, measurement input \| item	(0.23)
Non-recurring \| Maximum \| Commercial \| Income approach \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned, measurement input	0.1	0.10
Non-recurring \| Weighted average \| Discounted cash flow \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Servicing asset, measurement input \| item	0.13	0.09
Non-recurring \| Weighted average \| 1-4 family residential \| Sales comparison \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Impaired loans - measurement input \| item	0.21	0.07
Non-recurring \| Weighted average \| Agricultural \| Sales comparison \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned, measurement input \| item	0.13
Non-recurring \| Weighted average \| Commercial \| Income approach \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Other real estate owned, measurement input \| item	0.10	0.10

Fair value as of the balance sheet date of impaired financing receivables.

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Value input used to measure impaired loans.

+ References

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Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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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
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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Value of input used to measure servicing asset.

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