Note 1 - Business and Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Number of Reportable Segments	1
Equity Securities, FV-NI	$ 0	$ 0
Loans and Leases Receivable, Days Before Nonaccrual Status (Day)	90 days
Loans and Leases Receivable, Certain Consumer Loans and Auto Receivables, Days Before Chargeoff (Day)	120 days
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	15 years
Land and Land Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	20 years
Land and Land Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	50 years
Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	20 years

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482736/825-10-45-1A

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-18

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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- Definition

The duration before certain consumer loans and auto receivables will be charged off against the allowance for credit losses.

+ References

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- Definition

The duration available before delinquent loans are placed in nonaccrual status.

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