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Securities - Amortized cost and fair values of securities, with gross unrealized gains and losses (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Available-for-sale securities:
Amortized Cost	$ 39,367	$ 52,585
Unrealized Gains	9	61
Unrealized Losses	(3,594)	(3,493)
Allowance for Credit Losses	(666)	(518)	$ (498)	$ (498)
Fair Value	35,116	48,635
Assets pledged as collateral
Held-to-maturity securities:
Fair Value	17,800	27,800
Assets pledged as collateral \| Deposits with local municipalities
Available-for-sale securities:
Assets pledged, fair value	11,300	5,200
Investments at fair market value	10,600	4,700
Assets pledged as collateral \| Link deposit program
Available-for-sale securities:
Fair Value	1,900	1,400
Investments at fair market value	1,700	1,200
U.S. Treasury securities
Available-for-sale securities:
Amortized Cost	6,006	14,775
Unrealized Gains		36
Unrealized Losses	(46)	(16)
Fair Value	5,960	14,795
U.S. Government Agency securities
Available-for-sale securities:
Amortized Cost	1,000	1,000
Unrealized Losses	(107)	(100)
Fair Value	893	900
Municipal securities
Available-for-sale securities:
Amortized Cost	16,335	16,406
Unrealized Gains		3
Unrealized Losses	(2,381)	(2,364)
Allowance for Credit Losses	(666)	(518)
Fair Value	13,288	13,527
Mortgage-backed securities and collateralized mortgage obligations
Available-for-sale securities:
Amortized Cost	10,263	11,796
Unrealized Gains		10
Unrealized Losses	(990)	(891)
Fair Value	9,273	10,915
Corporate securities
Available-for-sale securities:
Amortized Cost	5,763	8,608
Unrealized Gains	9	12
Unrealized Losses	(70)	(122)
Fair Value	$ 5,702	$ 8,498