Note 6 - Loans and the Allowance for Credit Losses - Amortized Cost of of the Modified Loans (Details) $ in Thousands	3 Months Ended
Mar. 31, 2026 USD ($)
Modified	$ 41,453
Loans Modified, Gross	$ 11,739,093
Modified, percentage	0.35%
Extended Maturity [Member]
Modified	$ 38,005
Payment Deferral [Member]
Modified	2,849
Contractual Interest Rate Reduction [Member]
Modified	599
Commercial Portfolio Segment [Member]
Modified	11,759
Loans Modified, Gross	$ 1,644,836
Modified, percentage	0.71%
Weighted Average Term Extension (Month)	4 months
Weighted Average Interest Rate Reduction	2.00%
Commercial Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 8,311
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	2,849
Commercial Portfolio Segment [Member] \| Contractual Interest Rate Reduction [Member]
Modified	$ 599
Commercial Portfolio Segment [Member] \| Weighted Average [Member]
Payment Deferral (Month)	2 months
Commercial Real Estate Portfolio Segment [Member]
Modified	$ 29,694
Loans Modified, Gross	$ 8,318,844
Modified, percentage	0.36%
Weighted Average Term Extension (Month)	120 months
Commercial Real Estate Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 29,694
Commercial Real Estate Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	0
Commercial Real Estate Portfolio Segment [Member] \| Contractual Interest Rate Reduction [Member]
Modified	0
Commercial Construction Portfolio Segment [Member]
Modified	0
Loans Modified, Gross	$ 571,073
Modified, percentage	0.00%
Weighted Average Term Extension (Month)	124 months
Commercial Construction Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0
Commercial Construction Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	0
Commercial Construction Portfolio Segment [Member] \| Contractual Interest Rate Reduction [Member]
Modified	0
Residential Portfolio Segment [Member]
Modified	0
Loans Modified, Gross	$ 1,202,539
Modified, percentage	0.00%
Residential Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0
Residential Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	0
Residential Portfolio Segment [Member] \| Contractual Interest Rate Reduction [Member]
Modified	0
Consumer Portfolio Segment [Member]
Modified	0
Loans Modified, Gross	$ 1,801
Modified, percentage	0.00%
Consumer Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0
Consumer Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	0
Consumer Portfolio Segment [Member] \| Contractual Interest Rate Reduction [Member]
Modified	$ 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
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+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
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+ References

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Percentage of decrease in weighted-average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

+ References

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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 reported fact of one year, five months, and thirteen days.

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