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Note 2 - Securities - Credit Quality Indicators for Held to Maturity Securities (Details) - USD ($) $ in Thousands		Sep. 30, 2025	Dec. 31, 2024
Amortized cost, held to maturity securities		$ 104,691	$ 109,836
Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		35,447	35,292
Moody's, Aa1/Aa2/Aa3 Rating [Member]
Amortized cost, held to maturity securities		8,168	8,162
Moody's, Baa1/ Baa2/ Baa3 Rating [Member]
Amortized cost, held to maturity securities		3,000	3,000
Not Rated - Agency [Member]
Amortized cost, held to maturity securities	[1]	58,076	63,382
US Treasury Securities [Member]
Amortized cost, held to maturity securities		9,825	9,632
US Treasury Securities [Member] | Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		9,825	9,632
US Treasury Securities [Member] | Moody's, Aa1/Aa2/Aa3 Rating [Member]
Amortized cost, held to maturity securities		0	0
US Treasury Securities [Member] | Moody's, Baa1/ Baa2/ Baa3 Rating [Member]
Amortized cost, held to maturity securities		0	0
US Treasury Securities [Member] | Not Rated - Agency [Member]
Amortized cost, held to maturity securities	[1]	0	0
US Agency and Mortgage-backed Securities [Member]
Amortized cost, held to maturity securities		81,431	86,555
US Agency and Mortgage-backed Securities [Member] | Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		23,355	23,173
US Agency and Mortgage-backed Securities [Member] | Moody's, Aa1/Aa2/Aa3 Rating [Member]
Amortized cost, held to maturity securities		0	0
US Agency and Mortgage-backed Securities [Member] | Moody's, Baa1/ Baa2/ Baa3 Rating [Member]
Amortized cost, held to maturity securities		0	0
US Agency and Mortgage-backed Securities [Member] | Not Rated - Agency [Member]
Amortized cost, held to maturity securities	[1]	58,076	63,382
US States and Political Subdivisions Debt Securities [Member]
Amortized cost, held to maturity securities		10,435	10,649
US States and Political Subdivisions Debt Securities [Member] | Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		2,267	2,487
US States and Political Subdivisions Debt Securities [Member] | Moody's, Aa1/Aa2/Aa3 Rating [Member]
Amortized cost, held to maturity securities		8,168	8,162
US States and Political Subdivisions Debt Securities [Member] | Moody's, Baa1/ Baa2/ Baa3 Rating [Member]
Amortized cost, held to maturity securities		0	0
US States and Political Subdivisions Debt Securities [Member] | Not Rated - Agency [Member]
Amortized cost, held to maturity securities	[1]	0	0
Corporate Debt Securities [Member]
Amortized cost, held to maturity securities		3,000	3,000
Corporate Debt Securities [Member] | Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		0	0
Corporate Debt Securities [Member] | Moody's, Aa1/Aa2/Aa3 Rating [Member]
Amortized cost, held to maturity securities		0	0
Corporate Debt Securities [Member] | Moody's, Baa1/ Baa2/ Baa3 Rating [Member]
Amortized cost, held to maturity securities		3,000	3,000
Corporate Debt Securities [Member] | Not Rated - Agency [Member]
Amortized cost, held to maturity securities	[1]	$ 0	$ 0
[1] Generally considered not to have credit risk given the implied governmental guarantees associated with these agencies.

X

- Definition

Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

+ 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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