Fair Value Measurements - Fair value of assets measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Securities available-for-sale:
Securities available-for-sale, at fair value	$ 144,649	$ 169,993
Equity securities, at fair value	2,698	2,792
U.S. Treasuries
Securities available-for-sale:
Securities available-for-sale, at fair value	30,004	42,977
U.S. government and federal agencies
Securities available-for-sale:
Securities available-for-sale, at fair value	13,621	13,275
Corporate bonds
Securities available-for-sale:
Securities available-for-sale, at fair value	2,655	2,523
U.S. agency collateralized mortgage obligations
Securities available-for-sale:
Securities available-for-sale, at fair value	32,906	34,310
Tax-exempt municipal
Securities available-for-sale:
Securities available-for-sale, at fair value	1,221	1,231
Taxable municipal
Securities available-for-sale:
Securities available-for-sale, at fair value	261	587
U.S. agency mortgage-backed
Securities available-for-sale:
Securities available-for-sale, at fair value	63,981	75,090
Fair Value, Recurring
Securities available-for-sale:
Equity securities, at fair value	2,698	2,792
Total assets at fair value	147,968	173,631
Liabilities:
Total liabilities at fair value	621	846
Fair Value, Recurring | Interest Rate Swap
Securities available-for-sale:
Interest rate swap agreements	621
Total assets at fair value		846
Liabilities:
Interest rate swap agreements	621	846
Fair Value, Recurring | U.S. Treasuries
Securities available-for-sale:
Securities available-for-sale, at fair value	30,004	42,977
Fair Value, Recurring | U.S. government and federal agencies
Securities available-for-sale:
Securities available-for-sale, at fair value	13,621	13,275
Fair Value, Recurring | Corporate bonds
Securities available-for-sale:
Securities available-for-sale, at fair value	2,655	2,523
Fair Value, Recurring | U.S. agency collateralized mortgage obligations
Securities available-for-sale:
Securities available-for-sale, at fair value	32,906	34,310
Fair Value, Recurring | Tax-exempt municipal
Securities available-for-sale:
Securities available-for-sale, at fair value	1,221	1,231
Fair Value, Recurring | Taxable municipal
Securities available-for-sale:
Securities available-for-sale, at fair value	261	587
Fair Value, Recurring | U.S. agency mortgage-backed
Securities available-for-sale:
Securities available-for-sale, at fair value	63,981	75,090
Fair Value, Recurring | Fair Value, Inputs, Level 1
Securities available-for-sale:
Equity securities, at fair value	2,698	2,792
Total assets at fair value	2,698	2,792
Fair Value, Recurring | Fair Value, Inputs, Level 2
Securities available-for-sale:
Total assets at fair value	145,270	170,839
Liabilities:
Total liabilities at fair value	621	846
Fair Value, Recurring | Fair Value, Inputs, Level 2 | Interest Rate Swap
Securities available-for-sale:
Interest rate swap agreements	621
Total assets at fair value		846
Liabilities:
Interest rate swap agreements	621	846
Fair Value, Recurring | Fair Value, Inputs, Level 2 | U.S. Treasuries
Securities available-for-sale:
Securities available-for-sale, at fair value	30,004	42,977
Fair Value, Recurring | Fair Value, Inputs, Level 2 | U.S. government and federal agencies
Securities available-for-sale:
Securities available-for-sale, at fair value	13,621	13,275
Fair Value, Recurring | Fair Value, Inputs, Level 2 | Corporate bonds
Securities available-for-sale:
Securities available-for-sale, at fair value	2,655	2,523
Fair Value, Recurring | Fair Value, Inputs, Level 2 | U.S. agency collateralized mortgage obligations
Securities available-for-sale:
Securities available-for-sale, at fair value	32,906	34,310
Fair Value, Recurring | Fair Value, Inputs, Level 2 | Tax-exempt municipal
Securities available-for-sale:
Securities available-for-sale, at fair value	1,221	1,231
Fair Value, Recurring | Fair Value, Inputs, Level 2 | Taxable municipal
Securities available-for-sale:
Securities available-for-sale, at fair value	261	587
Fair Value, Recurring | Fair Value, Inputs, Level 2 | U.S. agency mortgage-backed
Securities available-for-sale:
Securities available-for-sale, at fair value	$ 63,981	$ 75,090