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Note 5 - Mortgage Loan Servicing (Tables) | 12 Months Ended
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Dec. 31, 2022
Notes Tables |
Mortgage Loans Serviced for Others [Table Text Block] |
|  | 2022 |  |  | 2021 |
Mortgage loan portfolios serviced for: |  |  |  |  |  |  |  |
Federal Home Loan Mortgage Corporation |  | $ | 1,345,312,000 |  |  | $ | 1,320,550,000 |
Federal Home Loan Bank |  |  | 30,831,000 |  |  |  | 23,505,000 |
Total mortgage loans serviced for others |  | $ | 1,376,143,000 |  |  | $ | 1,344,055,000 |
Servicing Asset at Amortized Cost [Table Text Block] |
|  | 2022 |  |  | 2021 |
Balance at beginning of year |  | $ | 12,248,000 |  |  | $ | 8,189,000 |
Additions |  |  | 2,773,000 |  |  |  | 7,711,000 |
Amortized to expense |  |  | (3,184,000 | ) |  |  | (3,652,000 | )
Balance at end of year |  | $ | 11,837,000 |  |  | $ | 12,248,000 |
Schedule of Mortgage Servicing Rights Future Amortization Expense [Table Text Block] |
2023 |  | $ | 2,366,000 |
2024 |  |  | 2,066,000 |
2025 |  |  | 1,772,000 |
2026 |  |  | 1,492,000 |
2027 |  |  | 1,236,000 |
Thereafter |  |  | 2,905,000 |

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- Definition Tabular disclosure of activity in the balance of servicing assets subsequently measured at amortized cost. Includes, but is not limited to, beginning and ending balances, additions, disposals, and amortization. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 4 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=128311188&loc=d3e122739-111746 + Details
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