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Note 3 - Loans and Allowance for Credit Losses (Details Textual) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Financing Receivable, before Allowance for Credit Loss, Total |  | $ 4,303,758 | $ 3,916,619 |
Financing Receivable, Nonaccrual, Interest Income |  | 200 | 100 | $ 100
Financing Receivable, Revolving, Converted to Term Loan During Period |  | 6,400 | 1,300 |
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease) |  | (2,000) | (1,700) |
Financing Receivable, Individually Evaluated for Impairment |  | 5,400 | 13,200 |
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment |  | 400 | 2,600 |
Commercial Portfolio Segment [Member] |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  | $ 3,415,299 | $ 3,131,830 |
Financing Receivables, Prepayment Speed Assumed |  | 2.00% | 2.00% |
Commercial Portfolio Segment [Member] | Commercial and Industrial, Credit Cards to Business Customers [Member] |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  | $ 17,800 | $ 16,600 |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | [1] | 332,609 | 266,468 |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | [1] | 1,035,684 | 979,214 |
Retail Portfolio Segment [Member] |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  | 888,459 | 784,789 |
Retail Portfolio Segment [Member] | Home Equity Loan [Member] |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total |  | 38,100 | 37,400 |
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | [2] | $ 837,406 | $ 755,036 |
Financing Receivables, Prepayment Speed Assumed |  | 9.00% | 16.10% |
Financing Receivables, Allowance for Credit Loss, Increase From Decrease of Prepayment Speed Assumed |  | $ 5,300 |  |
Retail Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | [3] | $ 51,053 | $ 29,753 |
Financing Receivables, Prepayment Speed Assumed |  | 9.00% | 9.00% |
Commercial Real Estate Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Reclassification Between Loan Segments [Member] |  |  |  |
Increase (Decrease) in Finance Receivables |  |  | $ 54,500 |
Commercial Real Estate Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] | Reclassification Between Loan Segments [Member] |  |  |  |
Increase (Decrease) in Finance Receivables |  |  | $ (54,500) |
[1] | We have reclassified multi-family construction loans from real estate - non-owner occupied loans to real estate - multi-family and residential rental loans. The table above reflects a classification change of $54.5 million as of December 31, 2022. All the tables that follow have been adjusted to reflect the reclassifications as of the applicable dates.
[2] | Home equity lines of credit were reclassified from 1-4 family mortgage loans to other consumer loans during the year ended December 31, 2023. Home equity lines of credit totaled $38.1 million and $37.4 million as of December 31, 2023, and 2022, respectively.
[3] | Credit cards to business customers were reclassified from other consumer loans to commercial and industrial during the year ended December 31, 2023. Credit cards to business customers totaled $17.8 million and $16.6 million as of December 31, 2023, and 2022, respectively.

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