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Note 2 - Securities - Credit Quality Indicators for Held to Maturity Securities (Details) - USD ($) $ in Thousands		Mar. 31, 2025	Dec. 31, 2024
Amortized cost, held to maturity securities		$ 108,379	$ 109,835
Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		35,410	35,292
Moody's, Aa1/Aa2/Aa3 Rating [Member]
Amortized cost, held to maturity securities		8,164	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]	61,805	63,381
US Treasury Securities [Member]
Amortized cost, held to maturity securities		9,696	9,632
US Treasury Securities [Member] | Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		9,696	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		85,038	86,554
US Agency and Mortgage-backed Securities [Member] | Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		23,233	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]	61,805	63,381
US States and Political Subdivisions Debt Securities [Member]
Amortized cost, held to maturity securities		10,645	10,649
US States and Political Subdivisions Debt Securities [Member] | Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		2,481	2,487
US States and Political Subdivisions Debt Securities [Member] | Moody's, Aa1/Aa2/Aa3 Rating [Member]
Amortized cost, held to maturity securities		8,164	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, 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 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482736/825-10-45-1A

Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-7A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-5

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-14

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