Note 6 - Loans and the Allowance for Credit Losses - Amortized Cost of of the Modified Loans (Details) $ in Thousands	6 Months Ended
Jun. 30, 2025 USD ($)
Modified	$ 34,371
Loans Modified, Gross	$ 11,169,138
Modified, percentage	0.31%
Extended Maturity [Member]
Modified	$ 14,910
Payment Deferral [Member]
Modified	19,461
Commercial Portfolio Segment [Member]
Modified	25,952
Loans Modified, Gross	$ 1,607,528
Modified, percentage	1.61%
Weighted Average Term Extension (Month)	3 months
Commercial Portfolio Segment [Member] \| Weighted Average [Member]
Payment Deferral (Month)	3 months
Commercial Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 6,491
Commercial Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	19,461
Commercial Real Estate Portfolio Segment [Member]
Modified	0
Loans Modified, Gross	$ 7,624,033
Modified, percentage	0.00%
Commercial Real Estate Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0
Commercial Real Estate Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	0
Commercial Construction Portfolio Segment [Member]
Modified	8,419
Loans Modified, Gross	$ 681,222
Modified, percentage	1.24%
Weighted Average Term Extension (Month)	6 months
Commercial Construction Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 8,419
Commercial Construction Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	0
Residential Portfolio Segment [Member]
Modified	0
Loans Modified, Gross	$ 1,254,646
Modified, percentage	0.00%
Residential Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0
Residential Portfolio Segment [Member] \| Payment Deferral [Member]
Modified	0
Consumer Portfolio Segment [Member]
Modified	0
Loans Modified, Gross	$ 1,709
Modified, percentage	0.00%
Consumer Portfolio Segment [Member] \| Extended Maturity [Member]
Modified	$ 0
Consumer Portfolio Segment [Member] \| Payment Deferral [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
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

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- Definition

Percentage of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

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- Definition

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
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

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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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