INCOME TAXES - Components of Net Deferred Tax Liability (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Components of net deferred tax liability
Investment securities	$ 157,456	$ 191,953
Allowance for loan losses	16,398	15,346
Employee benefits	5,727	5,775
Operating lease liabilities	10,211	7,552
Other, net	6,023	4,385
Deferred tax asset	195,815	225,011
Goodwill and intangibles	39,366	39,454
Operating lease right-of-use assets	9,872	7,303
Loan origination costs	10,777	9,731
Depreciation	383	96
Mortgage servicing rights	306	640
Pension	19,181	18,154
Deferred tax liability	79,885	75,378
Net deferred tax asset	$ 115,930	$ 149,633

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 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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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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Amount of deferred tax liability attributable to taxable temporary differences.

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

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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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 allowance, of deferred tax asset attributable to deductible temporary difference from allowance for credit loss on financing receivable.

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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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