Note 7 - Income Taxes - Tax Credits and Other Tax Benefits Recognized and Amortization Expense Related to Tax Credit Partnerships (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Tax credits and other tax benefits recognized	$ 3,551	$ 350
Tax credits and other tax benefits recognized, effective yield	0	399
Provision for Income Taxes [Member]
Amortization expense	2,853	398
Amortization expense, effective yield	0	0
Noninterest Expense [Member]
Amortization expense	0	323
Amortization expense, effective yield	$ 0	$ 0

Amount of amortization expense for investment that generates income tax credit and other income tax benefit under tax credit program accounted for using tax yield method.

No definition available.

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Amount, before amortization expense, of income tax credit and other tax benefit generated by investment under tax credit program elected to be accounted for using effective yield method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under tax yield method.

+ References

No definition available.

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- Definition

Amount, before amortization expense, of income tax credit and other tax benefit generated by investment under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 323
-SubTopic 740
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478156/323-740-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 323
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A

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Amount of amortization expense for investment that generates income tax credit and other income tax benefit under tax credit program accounted for using proportional amortization method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 740
-SubTopic 323
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478156/740-323-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 323
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A

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