Income Taxes (Components Of The Net Deferred Tax (Liabilities) Assets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Apr. 18, 2014	Dec. 31, 2013
Deferred Tax Assets, Gross [Abstract]
Net operating loss carryforwards	$ 197,227		$ 37
Loan discount	78,508		1,802
Allowance for loan and lease losses	41,133		33,665
Accrued severance and deferred compensation	28,216		13,442
Tax credits	21,966		5,716
Non-accrual loans	13,225umpq_DeferredTaxAssetsNonAccrualLoans		5,760umpq_DeferredTaxAssetsNonAccrualLoans
Covered loans	10,949umpq_DeferredTaxAssetsCoveredLoans		16,788umpq_DeferredTaxAssetsCoveredLoans
Unrealized loss on investment securities	0		3,304
Accrued bonuses	7,222		4,337
Other	24,876us-gaap_DeferredTaxAssetsOther		13,547us-gaap_DeferredTaxAssetsOther
Total gross deferred tax assets	423,322us-gaap_DeferredTaxAssetsGross		98,398us-gaap_DeferredTaxAssetsGross
Deferred Tax Liabilities, Gross [Abstract]
Fair market value adjustment on preferred securities	50,549		18,649
Mortgage servicing rights	48,496		18,855
FHLB Dividends	16,452		1,233
Intangibles	15,074		5,633
Prepaid expenses	14,911		2,683
Unrealized gain on investment securities	13,546		0
Deferred loan fees	12,091		7,525
Premises and equipment depreciation	8,180		7,447
Other	11,137us-gaap_DeferredTaxLiabilitiesOther		19,695us-gaap_DeferredTaxLiabilitiesOther
Total gross deferred tax liabilities	190,436us-gaap_DeferredIncomeTaxLiabilities		81,720us-gaap_DeferredIncomeTaxLiabilities
Valuation allowance	(3,366)		(51)
Net deferred tax assets (liabilities)	$ 229,520us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 276,800us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 16,627us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred tax assets, covered loans.

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Deferred Tax Assets, Discount on Trust Preferred Securities

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Deferred Tax Assets, Non Accrual Loans

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Deferred Tax Liabilities, Federal Home Loan Bank Dividend

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Deferred Tax Liability, Deferred Loan Fees

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Deferred Tax Liability, Fair Value Market Value Adjustment on Preferred Securities

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Deferred Tax Liability, Unrealized Gain on Investment Securities

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

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The tax effect as of the balance sheet date of the amount of future tax deductions arising from all unused tax credit carryforwards which have been reduced by a valuation allowance.

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-Glossary Carryforwards

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from employee bonuses.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from severance costs.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the allowance for doubtful accounts.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from unrealized losses on available-for-sale securities.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets including goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from mortgage servicing rights.

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Amount of deferred tax liability attributable to taxable temporary differences not separately disclosed.

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Amount of deferred tax consequences attributable to taxable temporary differences derived from prepaid expenses.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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