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Business Combinations and Asset Acquisitions - Schedule of purchase price (Details) - Umpqua Bank and Columbia Banking System Merger $ / shares in Units, shares in Thousands, $ in Thousands | Feb. 28, 2023 USD ($) $ / shares shares
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Asset Acquisition [Line Items] |
Business Acquisition Hypothetical Equity Interests Issued or Issuable | shares | 349,515
Business Combination, Consideration Transferred | $ 2,337,632
Columbia Banking System, Inc. |
Asset Acquisition [Line Items] |
Business Acquisition Hypothetical Equity Interests Issued or Issuable | shares | 132,365
UHC |
Asset Acquisition [Line Items] |
Business Acquisition Hypothetical Equity Interests Issued or Issuable | shares | 217,150
Business Acquisition Purchase Price | $ / shares | $ 17.66
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable | $ 2,337,567
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned | 65
Business Combination, Consideration Transferred | $ 2,337,632

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