Loans and Allowance for Credit Losses - Balances in Allowance for loan losses and Loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Allowance for credit losses:
Balance, beginning of year	$ 842	$ 700	$ 700
Provision charged to expense	(2)	45
Losses charged off			(3)
Balance, end of year	840	745	842
Ending balance: individually evaluated for impairment	6		7
Loans:
Ending balance	109,811		109,595
Ending balance: individually evaluated	789		729
Unfunded loan commitments
Allowance for credit losses:
Balance, beginning of year	20	17	17
Provision charged to expense	17	11
Balance, end of year	37	28	20
Mortgage loans on real estate
Loans:
Ending balance	100,806		100,158
Ending balance: individually evaluated	783		722
Mortgage loans on real estate \| Residential 1-4 family
Allowance for credit losses:
Balance, beginning of year	283	271	271
Provision charged to expense	(5)	(5)
Balance, end of year	278	266	283
Loans:
Ending balance	68,657		69,197
Ending balance: individually evaluated	311		245
Mortgage loans on real estate \| Residential 1-4 family \| Unfunded loan commitments
Allowance for credit losses:
Balance, beginning of year	2	2	2
Provision charged to expense	4	2
Balance, end of year	6	4	2
Mortgage loans on real estate \| Commercial
Allowance for credit losses:
Balance, beginning of year	449	339	339
Provision charged to expense	4	44
Balance, end of year	453	383	449
Loans:
Ending balance	30,254		29,428
Ending balance: individually evaluated	472		477
Mortgage loans on real estate \| Commercial \| Unfunded loan commitments
Allowance for credit losses:
Balance, beginning of year	11	7	7
Provision charged to expense	14	14
Balance, end of year	25	21	11
Mortgage loans on real estate \| Construction and Land Development
Allowance for credit losses:
Balance, beginning of year	11	13	13
Provision charged to expense	2	(2)
Balance, end of year	13	11	11
Loans:
Ending balance	1,895		1,533
Mortgage loans on real estate \| Construction and Land Development \| Unfunded loan commitments
Allowance for credit losses:
Balance, beginning of year	4	6	6
Provision charged to expense	(1)	(6)
Balance, end of year	3		4
Commercial loans
Allowance for credit losses:
Balance, beginning of year	74	60	60
Provision charged to expense	(2)	6
Balance, end of year	72	66	74
Loans:
Ending balance	5,592		5,700
Commercial loans \| Unfunded loan commitments
Allowance for credit losses:
Balance, beginning of year	3	2	2
Provision charged to expense		1
Balance, end of year	3	3	3
Consumer
Allowance for credit losses:
Balance, beginning of year	25	17	17
Provision charged to expense	(1)	2
Losses charged off			(3)
Balance, end of year	24	$ 19	25
Ending balance: individually evaluated for impairment	6		7
Loans:
Ending balance	3,413		3,737
Ending balance: individually evaluated	$ 6		$ 7

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount of allowance for credit loss on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis.

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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Amount of financing receivable individually evaluated for credit loss. Excludes financing receivable collectively evaluated for credit loss.

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