Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Allowance for credit losses	$ 5,414	$ 5,380
OREO	7	0
Accrued pension and post-retirement	718	752
Unrealized loss on securities available for sale	11,343	10,520
Unrealized loss on derivative instruments	1,020	913
Unrealized loss on securities transferred from available for sale to held to maturity	12	15
Restricted stock grants	367	323
Core deposit intangible	25	29
Investment in flow through entities	141	99
Other assets	26	24
Total deferred tax asset	19,073	18,055
Net deferred loan costs	(2,826)	(2,599)
Depreciation	(2,253)	(2,383)
Goodwill	(371)	(319)
Mortgage servicing rights	(398)	(457)
Unrealized gain on derivative instruments	(1,062)	(993)
Prepaid expense	(292)	(276)
Total deferred tax liability	(7,202)	(7,027)
Net deferred tax asset	$ 11,871	$ 11,028

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The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from post-retirement benefits and pension costs, which can only be deducted for tax purposes when actual costs are incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.

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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 from derivative instruments.

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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 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 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 derivatives.

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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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