FAIR VALUE DISCLOSURES, Changes in Fair Value for Financial Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Changes in fair value for financial assets [Abstract]
Equity securities at fair value		$ 167
Trading securities, net gains (losses)			$ (62)
Loans held for sale	$ 1,962	637	413
Capitalized mortgage loan servicing rights, net gains (losses)	(16,224)	(9,532)	(2,323)
Impairment charges recognized [Abstract]
Collateral dependent loans, carrying amount	9,100	3,400
Collateral dependent loans, valuation allowance	1,800	1,500
Additional provision for loan losses on impaired loans	700	1,300	1,300
Other real estate, carrying amount	100	60
Other real estate, valuation allowance	90	92	144	$ 123
Other real estate, additional charge	30	30	90
Securities [Member]
Changes in fair value for financial assets [Abstract]
Equity securities at fair value		167
Trading securities, net gains (losses)			(62)
Mortgage Loans [Member]
Changes in fair value for financial assets [Abstract]
Loans held for sale	1,962	637	413
Mortgage Loan Servicing, Net [Member]
Changes in fair value for financial assets [Abstract]
Capitalized mortgage loan servicing rights, net gains (losses)	$ (16,224)	$ (9,532)	$ (2,323)

Loans which are measured for impairment using the fair value of collaterals.

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The valuation allowance on loans measured for impairment, using the fair value of collaterals.

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Amount of unrealized gain (loss) on loans held for sale measured at fair value with change in fair value recognized in net income.

+ References

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Carrying amount of other real estate that are impaired, net reserves.

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Amount of unrealized gain (loss) on capitalized servicing rights measured at fair value with change in fair value recognized in net income.

+ References

No definition available.

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Amount of unrealized gain (loss) on investment in trading security measured at fair value with change in fair value recognized in net income.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period.

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