Business Combinations and Asset Acquisitions - Pro Forma (Details) - Umpqua Bank and Columbia Banking System Merger $ in Thousands	3 Months Ended
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

Business acquisition, pro forma net interest income

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- Definition

Business Acquisition, Pro Forma Non-interest Income

+ References

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Business Combination, Acquisition Related Costs - Combined for proforma

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 50
-Name Accounting Standards Codification
-Section 15
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480123/805-50-15-3

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479328/805-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479328/805-10-50-2

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