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Business Combinations and Asset Acquisitions - Pro Forma (Details) - Umpqua Bank and Columbia Banking System Merger $ in Thousands | 3 Months Ended
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Mar. 31, 2023 USD ($)
Asset Acquisition [Line Items] |
Business acquisition, pro forma net interest income | $ 526,260
Business Acquisition, Pro Forma Non-interest Income | 88,572
Business Acquisition, Pro Forma Net Income (Loss) | 217,135
Business Combination, Acquisition Related Costs - Combined for proforma | $ 143,900

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