Income Taxes - Summary of Net Deferred Tax Asset (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Gross deferred tax assets
Allowance for credit losses	$ 10,019	$ 10,336
Accrued retirement benefits		1,576
Unrealized losses on available for sale securities	982
Incentive compensation	1,905	1,591
Equity based compensation	1,347	1,343
Lease liabilities	9,458	10,455
ESOP dividends	193	166
Intangibles and fair value marks (merger related)	658	1,971
Other	265	226
Total gross deferred tax assets	24,827	27,664
Gross deferred tax liabilities
Deferred loan origination costs	(2,324)	(1,434)
Retirement benefits	(535)
Unrealized gains on available for sale securities		(641)
Depreciation of premises and equipment	(1,997)	(1,816)
Right of use asset	(8,733)	(9,751)
Mortgage servicing rights	(303)	(340)
Goodwill	(115)	(115)
Derivative transactions	(835)	(1,928)
Total gross deferred tax liabilities	(14,842)	(16,025)
Net deferred tax asset	$ 9,985	$ 11,639

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