Deposits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Deposit amount
Non-interest bearing	$ 66,757,000	$ 68,095,000
Savings accounts	739,036,000	910,652,000
Certificates of deposit	532,433,000	429,687,000
Money market	3,595,000	5,372,000
Checking and Super NOW	294,783,000	302,346,000
Total	$ 1,636,604,000	$ 1,716,152,000
Interest rate
Savings accounts (as a percent)	0.59%	0.13%
Certificates of deposit (as a percent)	4.11%	2.67%
Money market (as a percent)	0.10%	0.10%
Checking and Super NOW (as a percent)	0.02%	0.02%
Total (as a percent)	1.61%	0.74%
Maturity of certificate of deposit accounts
2022	$ 498,140,000
2023	20,142,000
2024	5,746,000
2025	3,743,000
2026	4,662,000
Total	532,433,000	$ 429,687,000
Interest expense by type of deposit
Savings	2,469,000	949,000
Certificates of deposit and money market	16,956,000	3,914,000
Checking and Super NOW	59,000	62,000
Total	19,484,000	4,925,000
Overdrawn deposit accounts reclassified as loans	169,000	35,000
Directors and executive officer
Interest expense by type of deposit
Deposits	4,500,000	3,900,000
Domestic
Deposit with balances greater than or equal to $250,000
Total	$ 280,100,000	$ 257,900,000