Commitments and Contingencies - Summary of outstanding loan commitments, unused lines of credit and letters of credit (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Commitments and Contingencies
Fair value disclosure, off-balance sheet risks, face amount, liability	$ 24,210	$ 21,438
Other mortgage loans
Commitments and Contingencies
Fair value disclosure, off-balance sheet risks, face amount, liability	8,952	9,280
Home-equity lines
Commitments and Contingencies
Fair value disclosure, off-balance sheet risks, face amount, liability	10,817	10,142
Commercial lines
Commitments and Contingencies
Fair value disclosure, off-balance sheet risks, face amount, liability	12,862	10,717
Unsecured consumer lines
Commitments and Contingencies
Fair value disclosure, off-balance sheet risks, face amount, liability	532	579
Letters of credit
Commitments and Contingencies
Fair value disclosure, off-balance sheet risks, face amount, liability	$ 45	$ 45