Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Allowance for credit losses	$ 3,115	$ 3,222
ASC 715 pension funding liability	987	1,594
Supplemental executive retirement plan accrual	2,328	2,311
Stock compensation	2,988	2,745
Unrealized loss on investment securities available-for-sale (1)	13,756	16,798
Research and development expenses	604	772
Lease liability	2,020	2,261
Other	330	640
Total deferred tax assets	26,128	30,343
Deferred tax liabilities:
Premises and equipment	(1,144)	(1,710)
Pension	(967)	(1,141)
Intangible assets	(1,828)	(1,744)
Right of use asset	(1,927)	(2,178)
Prepaid expenses	(765)	(847)
Other	(283)	(144)
Total deferred tax liabilities	(6,914)	(7,764)
Net deferred tax assets	$ 19,214	$ 22,579

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Deferred tax liabilities, pension costs.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-6

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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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, 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 long-lived assets other than property, plant, and equipment.

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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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