Loans and Leases - Activity in the allowance for loan and lease losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 3,440	$ 3,222	$ 3,222
Provision (credit) for credit losses	6	63
Loans charged-off	(10)	(13)
Recoveries	1	1
Ending balance	3,437	3,273	3,440
Loans and leases receivable
Ending balance	301,938		306,645
Construction and Land loan
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loans charged-off			(453)
Loans and leases receivable
Ending balance	42,693		48,372
Farmland loan
Loans and leases receivable
Ending balance	17,490		17,085
1-4 residential & multi-family
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Loans charged-off			(3)
Loans and leases receivable
Ending balance	149,145		151,326
Commercial real estate
Loans and leases receivable
Ending balance	63,985		61,526
Real estate
Loans and leases receivable
Ending balance	273,313		278,309
Real estate \| Construction and Land loan
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	591	632	632
Provision (credit) for credit losses		29
Ending balance	591	661	591
Loans and leases receivable
Ending balance	42,693		48,372
Real estate \| Farmland loan
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	152	74	74
Provision (credit) for credit losses	(2)	3
Ending balance	150	77	152
Loans and leases receivable
Ending balance	17,490		17,085
Real estate \| 1-4 residential & multi-family
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,399	1,355	1,355
Provision (credit) for credit losses	(49)	24
Loans charged-off		(3)
Ending balance	1,350	1,376	1,399
Loans and leases receivable
Ending balance	149,145		151,326
Real estate \| Commercial real estate
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	718	605	605
Provision (credit) for credit losses	33	14
Ending balance	751	619	718
Loans and leases receivable
Ending balance	63,985		61,526
Agriculture
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	1	1	1
Ending balance	1	1	1
Loans and leases receivable
Ending balance	44		33
Commercial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	407	375	375
Provision (credit) for credit losses	17	(16)
Ending balance	424	359	407
Loans and leases receivable
Ending balance	9,259		8,813
Municipalities
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	102	83	83
Provision (credit) for credit losses	(3)	10
Ending balance	99	93	102
Loans and leases receivable
Ending balance	15,229		14,890
Consumer and other
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	70	97	97
Provision (credit) for credit losses	10	(1)
Loans charged-off	(10)	(10)
Recoveries	1	1
Ending balance	71	$ 87	70
Loans and leases receivable
Ending balance	$ 4,093		$ 4,600

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

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- References

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