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Business Combinations and Asset Acquisitions - Narrative (Details) - USD ($) $ in Thousands |  | 12 Months Ended
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Oct. 01, 2021 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Bank of Commerce |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Purchase Price Allocation, Goodwill Amount | $ 57,330 |  |  |
Business Combination, Purchase Price Allocation, Amortizable Intangible Assets | 15,932 |  |  |
Business Combination, net loans acquired | 1,084,984 |  |  |
Acquired PCD loans | $ 40,278 |  |  |
Business Combination, Acquisition Related Costs |  | $ 10,370 | $ 0 | $ 0
Umpqua |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  | $ 4,100 |  |

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- Definition Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed. + References No definition available. + Details
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- Definition Fair value of acquired receivable from business combination, excluding certain loans and debt securities acquired in transfer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=123413009&loc=d3e4845-128472 + Details
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=123586518&loc=d3e1043-128460 + Details
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- Definition Amount at purchase price 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 (a) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919265-210447 + Details
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