INCOME TAXES, Components of Net Deferred Tax Liability (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Components of net deferred tax liability [Abstract]
Allowance for loan losses	$ 15,004	$ 12,059
Employee benefits	7,552	5,393
Operating lease liabilities	8,601	9,801
Other, net	900	837
Deferred tax asset	32,057	28,090
Investment securities	43,325	21,547
Goodwill and intangibles	40,802	39,189
Operating lease right-of-use assets	8,384	9,566
Loan origination costs	7,904	7,639
Depreciation	3,089	2,736
Mortgage servicing rights	291	162
Pension	16,987	13,769
Deferred tax liability	120,782	94,608
Net deferred tax liability	$ (88,725)	$ (66,518)

Amount before allocation of valuation allowances of deferred tax asset attributable to operating lease liabilities.

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The amount as of the balance sheet date of the estimated future tax effects attributable to the difference between the methods used to account for deferred loan origination costs for tax purposes and under generally accepted accounting principles which will increase future taxable income when such difference reverses.

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Amount of deferred tax liability attributable to taxable temporary differences from right-of-use assets.

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The amount as of the balance sheet date of the estimated future tax effects arising from unrealized gains on investments in debt and equity securities categorized as investing which will increase future taxable income when such gain is realized.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from employee benefits, classified as other.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the provision for loan losses.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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Amount of deferred tax liability attributable to taxable temporary differences from goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from mortgage servicing rights.

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Amount of deferred tax consequences attributable to taxable temporary differences derived from prepaid expenses.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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