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Securities - Amortized cost and fair values of securities, with gross unrealized gains and losses (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Available-for-sale securities:
Amortized Cost	$ 47,229	$ 52,585
Unrealized Gains	13	61
Unrealized Losses	(3,693)	(3,493)
Allowance for Credit Losses	(518)	(518)	$ (498)	$ (498)
FairValue	43,031	48,635
Assets pledged as collateral
Held-to-maturity securities:
Fair Value	23,800	27,800
Assets pledged as collateral \| Deposits with local municipalities
Available-for-sale securities:
Assets pledged, fair value	5,100	5,200
Investments at fair market value	4,500	4,700
Assets pledged as collateral \| Link deposit program
Available-for-sale securities:
FairValue	1,400	1,400
Investments at fair market value	1,200	1,200
U.S. Treasury securities
Available-for-sale securities:
Amortized Cost	11,764	14,775
Unrealized Gains	4	36
Unrealized Losses	(28)	(16)
FairValue	11,740	14,795
U.S. Government Agency securities
Available-for-sale securities:
Amortized Cost	1,000	1,000
Unrealized Losses	(107)	(100)
FairValue	893	900
Municipal securities
Available-for-sale securities:
Amortized Cost	16,368	16,406
Unrealized Gains		3
Unrealized Losses	(2,484)	(2,364)
Allowance for Credit Losses	(518)	(518)
FairValue	13,366	13,527
Mortgage-backed securities and collateralized mortgage obligations
Available-for-sale securities:
Amortized Cost	10,950	11,796
Unrealized Gains	2	10
Unrealized Losses	(951)	(891)
FairValue	10,001	10,915
Corporate securities
Available-for-sale securities:
Amortized Cost	7,147	8,608
Unrealized Gains	7	12
Unrealized Losses	(123)	(122)
FairValue	$ 7,031	$ 8,498