Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details Textual) Pure in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Financing Receivable, Threshold Period Past Due (Day)	90 days
Interest and Fee Income, Loans and Leases, Total	$ 8,100	$ 8,550
Financing Receivable, Troubled Debt Restructuring	$ 5,834	$ 4,285	$ 5,878
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Nonperforming Financial Instruments [Member]
Interest and Fee Income, Loans and Leases, Total	$ 0	$ 0	$ 0

Amount of financing receivable modified as troubled debt restructuring.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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Threshold period for when financing receivable is considered past due, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes threshold period past due to write off as uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447

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The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.1)
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