Loans and Leases (Schedule Of Major Types Of Loans And Leases) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Non-owner occupied term, net	$ 3,303,629	$ 3,290,610
Owner occupied term, net	2,577,484	2,633,864
Multifamily, net	2,764,403	2,638,618
Construction & development, net	238,303	258,722
Residential development, net	81,160	81,846
Term, net	1,128,986umpq_LoansReceivableCommercialTerm	1,102,987umpq_LoansReceivableCommercialTerm
LOC & other, net	1,275,871	1,322,722
Leases and equipment finance, net	570,492	523,114
Mortgage, net	2,330,325	2,233,735
Home equity loans & lines, net	863,269	852,478
Consumer & other, net	415,035	389,036
Total loans and leases, net of deferred fees and costs	$ 15,548,957	$ 15,327,732

Loans Receivable Commercial Leases and Equipment Finance

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- Definition

Loans Receivable Commercial LOC and Other

+ References

No definition available.

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- Definition

Loans Receivable Commercial Multifamily

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- Definition

Loans Receivable Commercial Owner Occupied Term

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No definition available.

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- Definition

Loans Receivable Commercial Residential Development

+ References

No definition available.

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- Definition

Loans Receivable Commercial Term

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No definition available.

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- Definition

Loans Receivable Commercial Term and Multifamily

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- Definition

Loans Receivable Commercial Construction

+ References

No definition available.

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- Definition

Amount before allowance of revolving, open-end loan, extended under a line of credit and secured by the borrower's residential property. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a)(3),(b))

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

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- Definition

Amount before allowance of consumer mortgage. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes subordinated loans such as home equity lines of credit and loans and leases covered under loss sharing agreements.

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- Definition

Amount before allowance of consumer loans and leases not otherwise specified in the taxonomy. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a)(7),(b))

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

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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