Note 5 - Loans - Non-accrual Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Non-accrual portfolio loans	$ 68,854	$ 65,846	$ 67,684
Interest Income Recognized	435	1,074	1,000
Nonaccrual Loans [Member]
Interest Income Recognized	4,620	4,032	3,093
Interest recognized	435	1,074	1,008
Net interest foregone	$ 4,185	$ 2,958	$ 2,085

Loans in non-accrual status classified as portfolio loans.

No definition available.

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(2)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(3)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554

+ Details

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Data Type:	xbrli:monetaryItemType
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: