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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Carrying amount of receivable assets originating from the indemnification agreement with the Federal Deposit Insurance Corporation (FDIC), in which the FDIC is to partially cover losses.

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No definition available.

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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).

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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

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Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Fair Value Measurement (Schedule Of Carrying Value And Fair Value Of Financial Instruments Not Recorded At Fair Value) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2013	Mar. 31, 2013
FINANCIAL ASSETS:
Cash and cash equivalents	$ 292,558us-gaap_CashAndDueFromBanks	$ 282,455us-gaap_CashAndDueFromBanks
Trading securities	10,452us-gaap_TradingSecurities	9,999us-gaap_TradingSecurities
Investment securities available for sale	2,535,121us-gaap_AvailableForSaleSecurities	2,298,555us-gaap_AvailableForSaleSecurities
Investment securities held to maturity	4,953us-gaap_HeldToMaturitySecurities	5,211us-gaap_HeldToMaturitySecurities
Loans held for sale, at fair value	406,487	286,802
Loans and leases, net	15,548,957	15,327,732	7,763,691
Restricted equity securities	117,218us-gaap_FederalHomeLoanBankStock	119,334us-gaap_FederalHomeLoanBankStock
Residential mortgage servicing rights	116,365us-gaap_ServicingAssetAtFairValueAmount	117,259us-gaap_ServicingAssetAtFairValueAmount	49,220us-gaap_ServicingAssetAtFairValueAmount	47,765us-gaap_ServicingAssetAtFairValueAmount
Bank owned life insurance assets	294,697us-gaap_BankOwnedLifeInsurance	294,296us-gaap_BankOwnedLifeInsurance
FDIC indemnification asset	1,861us-gaap_FDICIndemnificationAsset	4,417us-gaap_FDICIndemnificationAsset	4,417us-gaap_FDICIndemnificationAsset		18,362us-gaap_FDICIndemnificationAsset	23,174us-gaap_FDICIndemnificationAsset
FINANCIAL LIABILITIES:
Deposits	17,222,566us-gaap_Deposits	16,892,099us-gaap_Deposits
Securities sold under agreements to repurchase	321,202	313,321
Term debt	965,675umpq_TermDebt	1,006,395umpq_TermDebt
Junior subordinated debentures, at fair value	250,652	249,294
Junior subordinated debentures, at amortized cost	101,496	101,576
Carrying Value [Member]
FINANCIAL ASSETS:
Cash and cash equivalents	1,380,874	1,605,171
Trading securities	10,452	9,999
Investment securities available for sale	2,535,121	2,298,555
Investment securities held to maturity	4,953	5,211
Loans held for sale, at fair value	406,487	286,802
Loans and leases, net	15,428,853	15,211,565
Restricted equity securities	117,218	119,334
Residential mortgage servicing rights	116,365	117,259
Bank owned life insurance assets	294,697	294,296
FDIC indemnification asset	1,861	4,417
Derivatives	44,776	29,210
Visa Class B common stock	0	0
FINANCIAL LIABILITIES:
Deposits	17,222,566	16,892,099
Securities sold under agreements to repurchase	321,202	313,321
Term debt	965,675	1,006,395
Junior subordinated debentures, at fair value	250,652	249,294
Junior subordinated debentures, at amortized cost	101,496	101,576
Derivatives	44,344	30,785
Estimated Fair Value [Member]
FINANCIAL ASSETS:
Cash and cash equivalents	1,380,874	1,605,171
Trading securities	10,452	9,999
Investment securities available for sale	2,535,121	2,298,555
Investment securities held to maturity	5,429	5,554
Loans held for sale, at fair value	406,487	286,802
Loans and leases, net	15,499,091	15,252,083
Restricted equity securities	117,218	119,334
Residential mortgage servicing rights	116,365	117,259
Bank owned life insurance assets	294,697	294,296
FDIC indemnification asset	524	2,058
Derivatives	44,776	29,210
Visa Class B common stock	49,607	49,663
FINANCIAL LIABILITIES:
Deposits	17,228,286	16,893,890
Securities sold under agreements to repurchase	321,202	313,321
Term debt	978,769	1,018,948
Junior subordinated debentures, at fair value	250,652	249,294
Junior subordinated debentures, at amortized cost	74,240	73,840
Derivatives	$ 44,344	$ 30,785