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Business Combinations - Loan balances (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | Jul. 01, 2022 | Dec. 31, 2021 | Dec. 31, 2020
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Business Combinations |  |  |  |  |
Outstanding balance |  | $ 4,270 |  |  |
Carrying amount | $ 2,759,583 | 2,443,994 |  |  |
Allowance for credit losses on loans | 35,843 | 31,146 |  | $ 31,572 | $ 34,246
Carrying amount, net of allowance for loan losses | $ 2,723,740 | 2,412,848 |  |  |
MPB |  |  |  |  |
Business Combinations |  |  |  |  |
Carrying amount |  |  | $ 270,403 |  |
Evidence of deterioration of credit quality | MPB |  |  |  |  |
Business Combinations |  |  |  |  |
Outstanding balance |  | 175 |  |  |
Carrying amount |  | 151 |  |  |
Carrying amount, net of allowance for loan losses |  | 151 |  |  |
Evidence of deterioration of credit quality | MPB | Real estate construction |  |  |  |  |
Business Combinations |  |  |  |  |
Outstanding balance |  | $ 175 |  |  |

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