Note 6 - Loans and the Allowance for Credit Losses - Amortized Cost of of the Modified Loans (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025 USD ($)	Sep. 30, 2025 USD ($)
Modified	$ 18,811	$ 33,730
Loans Modified, Gross	$ 11,308,131	$ 11,308,131
Modified, percentage	0.17%	0.30%
Extended Maturity [Member]
Modified	$ 0	$ 14,919
Payment Deferral [Member]
Modified	18,811	18,811
Commercial Portfolio Segment [Member]
Modified	18,811	25,311
Loans Modified, Gross	$ 1,622,975	$ 1,622,975
Modified, percentage	1.16%	1.56%
Weighted Average Term Extension (Month)		3 months
Commercial Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0	$ 6,500
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	$ 18,811	$ 18,811
Commercial Portfolio Segment [Member] \| Weighted Average [Member]
Payment Deferral (Month)	3 months	3 months
Commercial Real Estate Portfolio Segment [Member]
Modified	$ 0	$ 0
Loans Modified, Gross	$ 7,721,070	$ 7,721,070
Modified, percentage	0.00%	0.00%
Commercial Real Estate Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0	$ 0
Commercial Real Estate Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	0	0
Commercial Construction Portfolio Segment [Member]
Modified	0	8,419
Loans Modified, Gross	$ 728,615	$ 728,615
Modified, percentage	0.00%	1.16%
Weighted Average Term Extension (Month)		6 months
Commercial Construction Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0	$ 8,419
Commercial Construction Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	0	0
Residential Portfolio Segment [Member]
Modified	0	0
Loans Modified, Gross	$ 1,233,305	$ 1,233,305
Modified, percentage	0.00%	0.00%
Residential Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0	$ 0
Residential Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	0	0
Consumer Portfolio Segment [Member]
Modified	0	0
Loans Modified, Gross	$ 2,166	$ 2,166
Modified, percentage	0.00%	0.00%
Consumer Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0	$ 0
Consumer Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	$ 0	$ 0

The gross amount of loans modified during the period.

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- Definition

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
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Period of payment deferral of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
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-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

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Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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