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Acquisitions - Pro forma Financial Information (Details) - Hancock Bancorp, Inc - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020
Business Acquisition [Line Items] |  |
Net interest income | $ 150,806 | $ 156,051
Net income | $ 53,714 | $ 55,958
Basic and diluted earnings per share | $ 4.07 | $ 4.08

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