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Loans and Allowance for Loan Losses - Aging of Past Due Loans by Class of Loan (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Financing Receivable, Past Due [Line Items] |  |
Loans | $ 4,420,633 | $ 4,147,691
Financial Asset, Current |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 4,413,322 | 4,141,558
30-59 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 3,888 | 4,395
60-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 899 | 822
Greater than 90 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 2,524 | 916
Financial Asset, Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 7,311 | 6,133
Construction Real Estate Loans |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 720,515 | 559,681
Construction Real Estate Loans | Financial Asset, Current |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 720,340 | 559,617
Construction Real Estate Loans | 30-59 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 175 | 43
Construction Real Estate Loans | 60-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 0 | 21
Construction Real Estate Loans | Greater than 90 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 0 | 0
Construction Real Estate Loans | Financial Asset, Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 175 | 64
1-4 Family Residential Real Estate Loans |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 689,492 | 663,519
1-4 Family Residential Real Estate Loans | Financial Asset, Current |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 686,096 | 659,408
1-4 Family Residential Real Estate Loans | 30-59 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 748 | 3,529
1-4 Family Residential Real Estate Loans | 60-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 685 | 368
1-4 Family Residential Real Estate Loans | Greater than 90 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 1,963 | 214
1-4 Family Residential Real Estate Loans | Financial Asset, Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 3,396 | 4,111
Commercial Real Estate Loans |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 2,117,306 | 1,987,707
Commercial Real Estate Loans | Financial Asset, Current |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 2,114,898 | 1,987,034
Commercial Real Estate Loans | 30-59 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 2,331 | 105
Commercial Real Estate Loans | 60-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 41 | 153
Commercial Real Estate Loans | Greater than 90 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 36 | 415
Commercial Real Estate Loans | Financial Asset, Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 2,408 | 673
Commercial loans |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 385,816 | 412,064
Commercial loans | Financial Asset, Current |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 384,635 | 411,025
Commercial loans | 30-59 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 494 | 515
Commercial loans | 60-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 162 | 277
Commercial loans | Greater than 90 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 525 | 247
Commercial loans | Financial Asset, Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 1,181 | 1,039
Municipal loans |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 441,512 | 450,067
Municipal loans | Financial Asset, Current |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 441,512 | 450,067
Municipal loans | 30-59 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 0 | 0
Municipal loans | 60-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 0 | 0
Municipal loans | Greater than 90 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 0 | 0
Municipal loans | Financial Asset, Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 0 | 0
Loans to individuals |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 65,992 | 74,653
Loans to individuals | Financial Asset, Current |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 65,841 | 74,407
Loans to individuals | 30-59 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 140 | 203
Loans to individuals | 60-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 11 | 3
Loans to individuals | Greater than 90 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | 0 | 40
Loans to individuals | Financial Asset, Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Loans | $ 151 | $ 246

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