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Note 3 - Loans and Allowance for Credit Losses - Age Analysis of Past Due Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Financing Receivable, before Allowance for Credit Loss	$ 4,698,019	$ 4,600,781
Recorded Balance 89 Days and Accruing	0	0
Commercial Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	3,821,158	3,707,304
Recorded Balance 89 Days and Accruing	0	0
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Financing Receivable, before Allowance for Credit Loss	1,375,368	1,287,308
Recorded Balance 89 Days and Accruing	0	0
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, before Allowance for Credit Loss	67,520	66,936
Recorded Balance 89 Days and Accruing	0	0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	725,106	748,837
Recorded Balance 89 Days and Accruing	0	0
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	1,134,012	1,128,404
Recorded Balance 89 Days and Accruing	0	0
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, before Allowance for Credit Loss	519,152	475,819
Recorded Balance 89 Days and Accruing	0	0
Retail Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	876,861	893,477
Recorded Balance 89 Days and Accruing	0	0
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Financing Receivable, before Allowance for Credit Loss	799,427	827,597
Recorded Balance 89 Days and Accruing	0	0
Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Financing Receivable, before Allowance for Credit Loss	77,434	65,880
Recorded Balance 89 Days and Accruing	0	0
Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, before Allowance for Credit Loss	757	2,494
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	0	17
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Financing Receivable, before Allowance for Credit Loss	0	5
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	12
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	757	2,477
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Financing Receivable, before Allowance for Credit Loss	654	2,365
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Financing Receivable, before Allowance for Credit Loss	103	112
Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, before Allowance for Credit Loss	1,513	713
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	1,305	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Financing Receivable, before Allowance for Credit Loss	1,305	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	208	713
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Financing Receivable, before Allowance for Credit Loss	208	713
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, before Allowance for Credit Loss	400	1,046
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	400	864
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Financing Receivable, before Allowance for Credit Loss	400	864
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	0	182
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Financing Receivable, before Allowance for Credit Loss	0	182
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, Past Due [Member]
Financing Receivable, before Allowance for Credit Loss	2,670	4,253
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	1,705	881
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Financing Receivable, before Allowance for Credit Loss	1,705	869
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	12
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, before Allowance for Credit Loss	0	0
Financial Asset, Past Due [Member] | Retail Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	965	3,372
Financial Asset, Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Financing Receivable, before Allowance for Credit Loss	862	3,260
Financial Asset, Past Due [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Financing Receivable, before Allowance for Credit Loss	103	112
Financial Asset, Not Past Due [Member]
Financing Receivable, before Allowance for Credit Loss	4,695,349	4,596,528
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	3,819,453	3,706,423
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Financing Receivable, before Allowance for Credit Loss	1,373,663	1,286,439
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, before Allowance for Credit Loss	67,520	66,924
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	725,106	748,837
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, before Allowance for Credit Loss	1,134,012	1,128,404
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, before Allowance for Credit Loss	519,152	475,819
Financial Asset, Not Past Due [Member] | Retail Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss	875,896	890,105
Financial Asset, Not Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Financing Receivable, before Allowance for Credit Loss	798,565	824,337
Financial Asset, Not Past Due [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Financing Receivable, before Allowance for Credit Loss	$ 77,331	$ 65,768

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