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Note 6 - Fair Value Measurements - Balances of Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Fair value, available for sale securities	$ 196,476	$ 163,847
Fair Value, Recurring [Member]
Fair value, available for sale securities	196,476	163,847
Derivatives - cash flow hedges	2,287	2,690
Assets, Fair Value	198,763	166,537
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value, available for sale securities	0	0
Derivatives - cash flow hedges	0	0
Assets, Fair Value	0	0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value, available for sale securities	196,476	163,847
Derivatives - cash flow hedges	2,287	2,690
Assets, Fair Value	198,763	166,537
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value, available for sale securities	0	0
Derivatives - cash flow hedges	0	0
Assets, Fair Value	0	0
US Treasury Securities [Member]
Fair value, available for sale securities	34,131	11,688
US Treasury Securities [Member] | Fair Value, Recurring [Member]
Fair value, available for sale securities	34,131	11,688
US Treasury Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value, available for sale securities	0	0
US Treasury Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value, available for sale securities	34,131	11,688
US Treasury Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value, available for sale securities	0	0
US Agency and Mortgage-backed Securities [Member]
Fair value, available for sale securities	106,642	98,039
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member]
Fair value, available for sale securities	106,642	98,039
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value, available for sale securities	0	0
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value, available for sale securities	106,642	98,039
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value, available for sale securities	0	0
Municipal Bonds [Member] | Fair Value, Recurring [Member]
Fair value, available for sale securities	55,703	54,120
Municipal Bonds [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value, available for sale securities	0	0
Municipal Bonds [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value, available for sale securities	55,703	54,120
Municipal Bonds [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value, available for sale securities	$ 0	$ 0

X

- Definition

Fair value portion of asset recognized for present right to economic benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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X

- Definition

Fair value of all asset derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4B
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4B

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4B

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X

- Definition

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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