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Note 3 - Loans and Allowance for Credit Losses (Details Textual) - USD ($) | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Dec. 31, 2021 | Dec. 31, 2022 | Jan. 01, 2022 | Dec. 31, 2020 | Aug. 08, 2020 | Dec. 31, 2019
Financing Receivable, before Allowance for Credit Loss, Total |  | $ 3,453,459,000 | $ 3,916,619,000 |  |  |  |
Financing Receivable, Accruing Trouble Debt Restructurings, Interest Income |  | 1,500,000 |  |  |  |  |
Interest Lost on Nonaccrual Loans |  | 100,000 |  |  |  |  |
Maximum [Member] |  |  |  |  |  |  |
Interest Lost on Nonaccrual Loans |  | 100,000 |  |  |  |  |
Collateral Dependent Loans [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  |  | 7,700,000 |  |  |  |
SBA, CARES Act, Paycheck Protection Program [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  |  |  |  |  | $ 554,000,000 |
Commercial Portfolio Segment [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  | 2,950,424,000 | 3,131,830,000 |  |  |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | [1] | 1,137,419,000 | 1,185,083,000 |  |  |  |
Financing Receivable, Troubled Debt Restructuring |  | 4,973,000 | 8,672,000 |  | $ 6,414,000 |  | $ 8,587,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Grades 1-4 [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | [2] | 729,224,000 | 719,583,000 |  |  |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | SBA, CARES Act, Paycheck Protection Program [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  | 40,100,000 | 900,000 |  | 365,000,000 |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | SBA, CARES Act, Paycheck Protection Program [Member] | Grades 1-4 [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  | 40,100,000 | 900,000 |  |  |  |
Retail Portfolio Segment [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  | 503,035,000 | 784,789,000 |  |  |  |
Retail Portfolio Segment [Member] | Home Equity Loan [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  | 29,500,000 | 37,400,000 |  |  |  |
Retail Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | [3] | 60,488,000 | 29,753,000 |  |  |  |
Financing Receivable, Troubled Debt Restructuring |  | 1,202,000 | 1,000 |  |  |  |
Retail Portfolio Segment [Member] | Other Consumer Loans [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring |  |  |  | $ (1,200,000) |  |  |
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  | 442,547,000 | 755,036,000 |  |  |  |
Financing Receivable, Troubled Debt Restructuring |  | $ 627,000 | $ 2,736,000 |  | $ 806,000 |  | $ 724,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring |  |  |  | $ 1,200,000 |  |  |
[1] | For December 31, 2022, and December 31, 2021, includes $0.9 million and $40.1 million in loans originated under the Paycheck Protection Program, respectively.
[2] | Included in Commercial and Industrial Loans Grades 1 – 4 are $40.1 million of loans originated under the Paycheck Protection Program.
[3] | In conjunction with the adoption of the CECL methodology effective January 1, 2022, home equity lines of credit were reclassified to 1-4 family mortgage loans from other consumer loans. Home equity lines of credit totaled $37.4 million and $29.5 million as of December 31, 2022, and 2021, respectively.

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