INCOME TAXES - Deferred tax assets and deferred tax liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Deferred tax assets
Allowance for credit losses	$ 2,232	$ 2,180
Unrealized losses on securities available for sale		384
Benefit plans	117	154
Accrued compensation	258	241
Other	87	253
Total deferred tax assets	2,694	3,212
Deferred tax liabilities
Postretirement benefits	(1,001)	(1,010)
Unrealized gains on securities available for sale	(26)
Depreciation	(330)	(330)
Goodwill	(407)	(407)
Funded status of pension plan	(196)	(109)
Other	(152)	(309)
Total deferred tax liabilities	(2,112)	(2,165)
Net deferred tax asset	$ 582	$ 1,047

Amount of deferred tax liability attributable to taxable temporary differences from funded status of pension plan.

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Amount of deferred tax liability attributable to taxable temporary differences from post retirement benefits.

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Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains on available for sale securities.

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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 allowances of deferred tax asset attributable to deductible temporary differences from postretirement benefits.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

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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, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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 classified as other.

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

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