Fair Value Measurements - Estimated fair values, and related carrying amounts, of financial instruments (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Financial assets
Securities held to maturity	$ 15,859	$ 16,744
Carrying Value
Financial assets
Cash and cash equivalents	6,454	6,450
Interest bearing deposits in banks	10,083	5,509
Securities held to maturity	17,521	18,283
Loans, net	297,463	301,986
Net investment in direct financing leases	1,038	1,219
Accrued interest receivable	1,683	1,888
Restricted investments carried at cost	2,805	2,773
Mortgage servicing rights	205	210
Financial liabilities
Deposits	331,957	327,904
FHLB advances	41,567	45,669
Accrued interest payable	639	683
Fair Value
Financial assets
Cash and cash equivalents	6,454	6,450
Interest bearing deposits in banks	10,083	5,509
Securities held to maturity	15,859	16,744
Loans, net	288,125	293,446
Net investment in direct financing leases	1,006	1,185
Accrued interest receivable	1,683	1,888
Restricted investments carried at cost	2,805	2,773
Mortgage servicing rights	205	210
Financial liabilities
Deposits	301,030	297,856
FHLB advances	42,049	46,478
Accrued interest payable	639	683
Level 1
Financial assets
Cash and cash equivalents	6,454	6,450
Interest bearing deposits in banks	10,083	5,509
Accrued interest receivable	1,683	1,888
Financial liabilities
Accrued interest payable	639	683
Level 2
Financial assets
Securities held to maturity	15,859	16,744
Restricted investments carried at cost	2,805	2,773
Level 3
Financial assets
Loans, net	288,125	293,446
Net investment in direct financing leases	1,006	1,185
Mortgage servicing rights	205	210
Financial liabilities
Deposits	301,030	297,856
FHLB advances	$ 42,049	$ 46,478

Fair value portion of interest bearing deposits in banks.

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- Definition

Fair value portion of interest payable.

+ References

No definition available.

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- Definition

Fair value portion of interest receivable.

+ References

No definition available.

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- Definition

Fair value portion of net investment in direct financing leases.

+ References

No definition available.

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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- References

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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The aggregate value of all restricted investments.

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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