Note 6 - Securities - Securities Available-for-sale by Contractual Maturity (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Less Than One Year, Amortized Cost	$ 17,287
Less Than One Year, Fair Value	17,126
One to Five Years, Amortized Cost	181,791
One to Five Years, Fair Value	171,117
Over Five to Ten Years, Amortized Cost	384,160
Over Five to Ten Years, Fair Value	349,660
Over Ten Years, Amortized Cost	380,740
Over Ten Years, Fair Value	341,668
Amortized Cost	963,978
Fair Value	$ 879,571

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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