Note 4 - Investment Securities (Details Textual) $ in Millions	3 Months Ended
Jun. 30, 2022 USD ($)	Dec. 31, 2021
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	470	213
Debt Securities, Available-for-sale, Amortized Cost, Transfer, Amount	$ 245.5
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	49
US Government Agencies Debt Securities [Member] \| Measurement Input, Loss Severity [Member]
Debt Securities, Available-for-Sale, Measurement Input	0.0631
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	140
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Measurement Input, Loss Severity [Member]
Debt Securities, Available-for-Sale, Measurement Input	0.1055
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	281
US States and Political Subdivisions Debt Securities [Member] \| Measurement Input, Loss Severity [Member]
Debt Securities, Available-for-Sale, Measurement Input	0.1201

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale transferred to investment in debt security measured at amortized cost (held-to-maturity).

No definition available.

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- Definition

Value of input used to measure 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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922888-210455

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