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Business Combinations and Asset Acquisitions - Schedule of common stock (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, Equity Interest Issued or Issuable, Number of Shares | shares | 208,241
Business Acquisition, Percentage of Voting Interests Acquired | 100.00%
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned | $ | $ 6,191,008
Columbia Banking System, Inc. |
Asset Acquisition [Line Items] |
Business Acquisition, Share Price | $ / shares | $ 29.73
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares | 78,863
Business Acquisition, Percentage of Voting Interests Acquired | 37.90%
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned | $ | $ 2,344,600
UHC |
Asset Acquisition [Line Items] |
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares | 129,378
Business Acquisition, Percentage of Voting Interests Acquired | 62.10%
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned | $ | $ 3,846,408

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