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Mergers and Acquisitions - Pro Forma Summary (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Current Year Acquisitions |  |  |
Pro Forma Information |  |  |
Net interest income and non-interest income | $ 886,370 | $ 898,761 |
Net income | $ 296,940 | 309,902 |
Previous Acquisitions |  |  |
Pro Forma Information |  |  |
Net interest income and non-interest income |  | 777,869 | $ 664,789
Net income |  | $ 265,289 | $ 218,365

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