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

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- Definition

Mortgage Loans on Real Estate, Repurchase Reserve Liability

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- Definition

Number Of Stores Consolidated

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- Definition

Standby Letters Of Credit Expire Thereafter

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No definition available.

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- Definition

Standby Letters Of Credit Expires Within One Year

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No definition available.

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- Definition

Standby Letters Of Credit, Financial Guarantees required to perform on

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- Definition

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

+ References

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- 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.

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No definition available.

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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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Commitments and Contingencies (Narrative) (Details) $ in Thousands		1 Months Ended	2 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 12, 2021 shares	Apr. 30, 2021 branches	Nov. 30, 2021 branches	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Financial guarantees in connection with standby letters of credit				$ 0	$ 0	$ 0	$ 0
Standby letters of credit expiring within one year				113,400		113,400
Standby letters of credit expiring thereafter				8,700		8,700
Residential mortgage loan repurchase reserve liability				$ 545		$ 545
Concentration Risk [Line Items]
Number Of Stores Consolidated \| branches		12
Subsequent Event
Concentration Risk [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Share Exchange Ratio \| shares	0.5958
Subsequent Event \| Umpqua Bank and Columbia Banking System Merger
Concentration Risk [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	62.00%
Subsequent Event \| Umpqua Bank and Columbia Banking System Merger \| Columbia Banking System, Inc.
Concentration Risk [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	38.00%
Expected
Concentration Risk [Line Items]
Number Of Stores Consolidated \| branches			15
Product Concentration Risk \| Revenue Benchmark \| Real Estate Loans As Part Of Loan Portfolio
Concentration Risk [Line Items]
Concentration risk (as a percent)						75.00%		71.00%