Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

Collateral posting requirements for clearing members and clearing houses

+ References

No definition available.

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- Definition

Counterparty Default Loss On Forward Contract

+ References

No definition available.

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- Definition

Termination value of derivatives in net liability position.

+ References

No definition available.

+ Details

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- Definition

Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.(a),19)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.17)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.25)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of credit risk valuation adjustment to derivative assets to properly reflect the credit quality of the counterparties.

+ References

No definition available.

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579245-113959

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-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5580258-113959

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Derivatives (Narrative) (Details) (USD $)	3 Months Ended
Derivatives (Narrative) (Details) (USD $)	Mar. 31, 2015 contracts	Mar. 31, 2014	Dec. 31, 2014
Credit Derivatives [Line Items]
Counterparty default losses on forward contracts	$ 0	$ 0
Commitments and contingent liabilities
Number of interest rate derivatives held	325
Termination value of derivatives in net liability position	41,000,000
CollateralPostingClearing	59,500,000umpq_CollateralPostingClearing		43,500,000umpq_CollateralPostingClearing
Decrease in settlement values of the Bank's derivative assets	(2,700,000)
Interest Rate Forward Sales Commitments [Member]
Credit Derivatives [Line Items]
Commitments and contingent liabilities	692,900,000
Commitments To Originate Loans Held For Sale [Member]
Credit Derivatives [Line Items]
Commitments and contingent liabilities	458,378,000
Interest Rate Swap [Member]
Credit Derivatives [Line Items]
Notional amount of credit risk derivatives	$ 1,500,000,000