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Note 2 - Securities - Credit Quality Indicators for Held to Maturity Securities (Details) - USD ($) $ in Thousands		Dec. 31, 2023	Dec. 31, 2022
Amortized cost, held to maturity securities		$ 148,351	$ 153,158
Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		64,828	64,043
Moody's, Aa1/Aa2/Aa3 Rating [Member]
Amortized cost, held to maturity securities		8,842	9,447
Moody's, A1/A2/A3 Rating [Member]
Amortized cost, held to maturity securities		0
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]	71,681	76,668
Not Rated - Non Agency [Member]
Amortized cost, held to maturity securities		0	0
US Treasury Securities [Member]
Amortized cost, held to maturity securities		39,085	38,211
US Treasury Securities [Member] | Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		39,085	38,211
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, A1/A2/A3 Rating [Member]
Amortized cost, held to maturity securities		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 Treasury Securities [Member] | Not Rated - Non Agency [Member]
Amortized cost, held to maturity securities		0	0
US Agency and Mortgage-backed Securities [Member]
Amortized cost, held to maturity securities		94,617	99,374
US Agency and Mortgage-backed Securities [Member] | Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		22,936	22,706
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, A1/A2/A3 Rating [Member]
Amortized cost, held to maturity securities		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]	71,681	76,668
US Agency and Mortgage-backed Securities [Member] | Not Rated - Non Agency [Member]
Amortized cost, held to maturity securities		0	0
US States and Political Subdivisions Debt Securities [Member]
Amortized cost, held to maturity securities		11,649	12,573
US States and Political Subdivisions Debt Securities [Member] | Moody's, Aaa Rating [Member]
Amortized cost, held to maturity securities		2,807	3,126
US States and Political Subdivisions Debt Securities [Member] | Moody's, Aa1/Aa2/Aa3 Rating [Member]
Amortized cost, held to maturity securities		8,842	9,447
US States and Political Subdivisions Debt Securities [Member] | Moody's, A1/A2/A3 Rating [Member]
Amortized cost, held to maturity securities		0
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
US States and Political Subdivisions Debt Securities [Member] | Not Rated - Non Agency [Member]
Amortized cost, held to maturity securities		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, A1/A2/A3 Rating [Member]
Amortized cost, held to maturity securities		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
Corporate Debt Securities [Member] | Not Rated - Non Agency [Member]
Amortized cost, held to maturity securities		$ 0	$ 0
[1] Generally considered not to have credit risk given the 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 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 3: 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

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-SubTopic 10
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-7A

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