Commitments and Contingencies - Summary of outstanding loan commitments, unused lines of credit and letters of credit (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value disclosure, off-balance sheet risks, face amount, liability	$ 25,304	$ 29,332
Other Mortgage Loans [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value disclosure, off-balance sheet risks, face amount, liability	2,863	2,229
Line Of Credit Home Equity [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value disclosure, off-balance sheet risks, face amount, liability	9,224	8,672
Line Of Credit Commercial [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value disclosure, off-balance sheet risks, face amount, liability	15,432	19,982
Line Of Credit Consumer Unsecured [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value disclosure, off-balance sheet risks, face amount, liability	648	678
Letter Of Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair value disclosure, off-balance sheet risks, face amount, liability	$ 55	$ 1,044