Note 4 - Loans, Allowance for Credit Losses and Credit Quality - Schedule of Nonaccrual Loans (Details) - USD ($)	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Total nonaccrual loans, with allowance for credit loss	$ 0		$ 0		$ 0
Total nonaccrual loans, without allowance for credit loss	1,286,000		1,286,000		1,957,000
Total loans, nonaccrual	1,286,000		1,286,000		1,957,000
Interest Income recognized	10,000	$ 17,000	49,000	$ 35,000	54,000
Real Estate Portfolio Segment [Member] \| One-to-four Family Residential Loan [Member]
Total nonaccrual loans, with allowance for credit loss	0		0		0
Total nonaccrual loans, without allowance for credit loss	982,000		982,000		1,872,000
Total loans, nonaccrual	982,000		982,000		1,872,000
Interest Income recognized			32,000		53,000
Real Estate Portfolio Segment [Member] \| Home Equity Loan [Member]
Total nonaccrual loans, with allowance for credit loss	0		0		0
Total nonaccrual loans, without allowance for credit loss	304,000		304,000		85,000
Total loans, nonaccrual	$ 304,000		304,000		85,000
Interest Income recognized			$ 17,000		$ 1,000

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status with allowance for credit loss. Excludes net investment in lease.

No definition available.

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- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. 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 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status with no allowance for credit loss. 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 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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