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Loans and Allowance for Loan Losses - Loans by Portfolio Segment (Details) - USD ($) $ in Thousands | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | --- | --- | ---
Loans and Leases Receivable Disclosure [Abstract] |  |  |  |  |  |
Loans | $ 4,329,043 |  | $ 4,147,691 |  |  |
Less: Allowance for loan losses | 36,303 | $ 36,332 | 36,515 | $ 35,449 | $ 35,524 | $ 35,273
Total loans | 4,292,740 |  | 4,111,176 |  |  |
Construction Real Estate Loans |  |  |  |  |  |
Loans and Leases Receivable Disclosure [Abstract] |  |  |  |  |  |
Loans | 657,354 |  | 559,681 |  |  |
Less: Allowance for loan losses | 3,395 | 3,152 | 3,164 | 3,399 | 3,604 | 3,787
1-4 Family Residential Real Estate Loans |  |  |  |  |  |
Loans and Leases Receivable Disclosure [Abstract] |  |  |  |  |  |
Loans | 684,878 |  | 663,519 |  |  |
Less: Allowance for loan losses | 2,660 | 2,314 | 2,173 | 2,024 | 1,982 | 1,866
Commercial Real Estate Loans |  |  |  |  |  |
Loans and Leases Receivable Disclosure [Abstract] |  |  |  |  |  |
Loans | 2,100,338 |  | 1,987,707 |  |  |
Less: Allowance for loan losses | 28,012 | 28,721 | 28,701 | 27,221 | 27,225 | 26,980
Commercial loans |  |  |  |  |  |
Loans and Leases Receivable Disclosure [Abstract] |  |  |  |  |  |
Loans | 383,724 |  | 412,064 |  |  |
Less: Allowance for loan losses | 2,017 | 1,901 | 2,235 | 2,558 | 2,454 | 2,397
Municipal loans |  |  |  |  |  |
Loans and Leases Receivable Disclosure [Abstract] |  |  |  |  |  |
Loans | 435,211 |  | 450,067 |  |  |
Less: Allowance for loan losses | 37 | 44 | 45 | 46 | 48 | 47
Loans to individuals |  |  |  |  |  |
Loans and Leases Receivable Disclosure [Abstract] |  |  |  |  |  |
Loans | 67,538 |  | 74,653 |  |  |
Less: Allowance for loan losses | $ 182 | $ 200 | $ 197 | $ 201 | $ 211 | $ 196

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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479344/326-20-45-1 + Details
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