Business Acquisition, Equity Interest Issued or Issuable, Share Exchange Ratio

No definition available.

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- Definition

Standby Letters Of Credit Expire Thereafter

+ References

No definition available.

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- Definition

Standby Letters Of Credit Expires Within One Year

+ References

No definition available.

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- Definition

Standby Letters Of Credit, Financial Guarantees required to perform on

+ References

No definition available.

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- Definition

Termination Fee

+ References

No definition available.

+ Details

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- References

No definition available.

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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

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
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Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Financial guarantees in connection with standby letters of credit		$ 0.0	$ 0.0	$ 0.0	$ 0.0
Standby letters of credit expiring within one year		107.7		107.7
Standby letters of credit expiring thereafter		$ 9.6		$ 9.6
Expected
Concentration Risk [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Share Exchange Ratio	0.5958
Termination Fee	$ 145.0
Expected \| Umpqua Bank and Columbia Banking System Merger
Concentration Risk [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	62.00%
Expected \| Umpqua Bank and Columbia Banking System Merger \| Columbia Banking System, Inc.
Concentration Risk [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	38.00%
Product Concentration Risk \| Revenue Benchmark \| Real Estate Loans As Part Of Loan Portfolio
Concentration Risk [Line Items]
Concentration risk (as a percent)				78.00%		76.00%