FAIR VALUE MEASUREMENTS - Unobservable Inputs Non-recurring (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Quantitative information about the significant unobservable inputs within Level 3
Premises held for sale	$ 1,800,000	$ 0
Non-recurring \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Total	17,926,000	22,446,000
Non-recurring \| Fair value of collateral - appraised value \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Impaired loans	6,137,000	11,676,000
Other real estate owned	2,236,000	2,351,000
Premises held for sale	1,764,000
Non-recurring \| Discounted cash flow \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Impaired loans	3,488,000	3,537,000
Capitalized servicing rights	4,301,000	4,882,000
Non-recurring \| Impaired loans \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Impaired loans	9,625,000	15,213,000
Non-recurring \| Impaired loans \| Minimum \| Fair value of collateral - appraised value \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Appraised value	$ 0	$ 0
Non-recurring \| Impaired loans \| Minimum \| Discounted cash flow \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Discount rate	2.88%	2.88%
Cash flows	$ 22,000	$ 22,000
Non-recurring \| Impaired loans \| Maximum \| Fair value of collateral - appraised value \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Appraised value	$ 6,915,000	$ 6,915,000
Non-recurring \| Impaired loans \| Maximum \| Discounted cash flow \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Discount rate	9.50%	9.50%
Cash flows	$ 1,002,000	$ 1,072,000
Non-recurring \| Capitalized servicing rights \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Capitalized servicing rights	4,301,000	4,882,000
Non-recurring \| Other real estate owned \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Other real estate owned	2,236,000	2,351,000
Non-recurring \| Other real estate owned \| Fair value of collateral - appraised value \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Appraised value	$ 2,695,000	2,700,000
Non-recurring \| Other real estate owned \| Minimum \| Fair value of collateral - appraised value \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Selling Costs	10.00%
Non-recurring \| Other real estate owned \| Maximum \| Fair value of collateral - appraised value \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Selling Costs	20.00%
Non-recurring \| Premises held for sale \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Premises held for sale	$ 1,764,000	$ 0
Non-recurring \| Premises held for sale \| Minimum \| Fair value of collateral - appraised value \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Appraised value	136,000
Non-recurring \| Premises held for sale \| Maximum \| Fair value of collateral - appraised value \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Appraised value	$ 527,000
Measurement Input, Constant Prepayment Rate \| Non-recurring \| Capitalized servicing rights \| Discounted cash flow \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Constant prepayment rate (CPR)		8.19%
Measurement Input, Discount Rate \| Non-recurring \| Capitalized servicing rights \| Discounted cash flow \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Discount rate	10.07%	10.08%
Measurement Input, Discount Rate \| Non-recurring \| Other real estate owned \| Discounted cash flow \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Selling Costs		12.93%
Measurement Input, Discount Rate \| Non-recurring \| Premises held for sale \| Discounted cash flow \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Selling Costs	6.00%
Measurement Input, Prepayment Rate \| Non-recurring \| Capitalized servicing rights \| Discounted cash flow \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Constant prepayment rate (CPR)	9.95%
Measurement Input, Loss Severity \| Non-recurring \| Impaired loans \| Minimum \| Fair value of collateral - appraised value \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Loss severity	0.00%	0.00%
Measurement Input, Loss Severity \| Non-recurring \| Impaired loans \| Maximum \| Fair value of collateral - appraised value \| Level 3
Quantitative information about the significant unobservable inputs within Level 3
Loss severity	55.00%	55.00%

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- Definition

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Represents the amount of impaired loans assets reported on the balance sheet at period end measured at fair value by the entity.

+ References

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+ References

No definition available.

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+ References

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

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

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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

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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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.

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- Definition

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

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Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

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