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Business Combinations and Asset Acquisitions - PCD Loans (Details) - USD ($) $ in Thousands |  | 3 Months Ended
--- | --- | ---
Feb. 28, 2023 | Mar. 31, 2023
Asset Acquisition [Line Items] |  |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date |  | $ 26,492
Umpqua Bank and Columbia Banking System Merger |  |
Asset Acquisition [Line Items] |  |
Financing Receivable, Purchased with Credit Deterioration, Amount at Par Value | $ 478,648 |
Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date | 26,492 |
Financing Receivable, Purchased with Credit Deterioration, Discount (Premium) | (49,337) |
Financing Receivable, Purchased with Credit Deterioration, Amount at Purchase Price | $ 402,819 |

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- Definition Amount of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 19 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919265-210447 + Details
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- Definition Amount of discount (premium) attributable to other factors on financing receivable purchased with credit deterioration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 19 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919265-210447 + Details
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