Cash and cash equivalents general maturity.

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- Definition

Federal home loan bank stock, minimum investment

+ References

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- Definition

Number Of Wholly Owned Trusts

+ References

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Expiration Period

+ References

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- Definition

Unallocated Allowance Maximum Amount

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2420-110228

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 325

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6478792&loc=d3e63345-112809

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Summary of Significant Accounting Policies (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014 trust	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Number Of Wholly Owned Trusts	25umpq_NumberOfWhollyOwnedTrusts
Cash And Cash Equivalents General Maturity	90 days
Unallocated Allowance Maximum Amount	5.00%umpq_UnallocatedAllowanceMaximumAmount
Federal Home Loan Bank Stock	$ 119,334,000us-gaap_FederalHomeLoanBankStock	$ 30,685,000us-gaap_FederalHomeLoanBankStock
Impairment charges related to SBA/USDA servicing assets	0us-gaap_AssetImpairmentCharges	0us-gaap_AssetImpairmentCharges	0us-gaap_AssetImpairmentCharges
Land and Building [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	39 years
Minimum [Member] \| Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Maximum [Member] \| Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Investment in Federal Home Loan Bank Stock [Member]
Property, Plant and Equipment [Line Items]
Federal Home Loan Bank Stock	117,900,000	29,400,000
Federal home loan bank stock, minimum investment	$ 56,100,000
2013 Stock Incentive Plan [Member]
Property, Plant and Equipment [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Expiration Period	10 years
2013 Stock Incentive Plan [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Share-based compensation award, vesting period	3 years
2013 Stock Incentive Plan [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Share-based compensation award, vesting period	5 years