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	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Tax credits and other tax benefits recognized	$ 3,469	$ 350	$ 7,122	$ 700
Tax credits and other tax benefits recognized	0	398	0	799
Provision for Income Taxes [Member]
Amortization expense in provision for income taxes	2,920	398	5,826	797
Amortization expense in provision for income taxes	0	0	0	0
Noninterest Expense [Member]
Amortization expense in provision for income taxes	0	323	0	647
Amortization expense in provision for income taxes	$ 0	$ 0	$ 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
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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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