Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]

No definition available.

Name:	umpq_FinancingReceivableAllowanceforCreditLossLoansAndLeasesAbstract
Namespace Prefix:	umpq_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

+ References

+ Details

Name:	us-gaap_AllowanceForLoanAndLeaseLossRecoveryOfBadDebts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

Name:	us-gaap_AllowanceForLoanAndLeaseLossesRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossAdditionalInformationAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

+ Details

Name:	us-gaap_LoansAndLeasesReceivableAllowance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

+ Details

Name:	us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_NotesReceivableNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

+ Details

Name:	us-gaap_ProvisionForLoanAndLeaseLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_CreditLossStatusAxis=us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Allowance for Loan and Lease Loss and Credit Quality (Activity In The Allowance For Loan And Lease Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period, allowance	$ 144,871	$ 140,608
Charge-offs	(17,152)	(15,812)
Recoveries	3,469	3,481
Provision	13,684	13,656
Balance, end of period, allowance	144,872	141,933
Allowance for loans and leases:
Collectively evaluated for impairment			$ 142,528		$ 138,628
Individually evaluated for impairment			139		605
Total	144,871	140,608	144,872	$ 144,871	141,933
Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]
Collectively evaluated for impairment			20,245,077		19,029,940
Individually evaluated for impairment			37,076		51,915
Total			20,405,997	20,422,666	19,255,347
Receivables Acquired with Deteriorated Credit Quality
Allowance for loans and leases:
Loans acquired with deteriorated credit quality			2,205		2,700
Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]
Loans acquired with deteriorated credit quality			123,844	134,500	173,492
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period, allowance	47,904	45,765
Charge-offs	(2,151)	(311)
Recoveries	337	217
Provision	1,751	334
Balance, end of period, allowance	47,841	46,005
Allowance for loans and leases:
Collectively evaluated for impairment			46,107		43,546
Individually evaluated for impairment			136		600
Total	47,904	45,765	47,841	47,904	46,005
Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]
Collectively evaluated for impairment			10,003,966		9,626,236
Individually evaluated for impairment			20,366		27,872
Total			10,121,626		9,790,489
Commercial real estate \| Receivables Acquired with Deteriorated Credit Quality
Allowance for loans and leases:
Loans acquired with deteriorated credit quality			1,598		1,859
Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]
Loans acquired with deteriorated credit quality			97,294		136,381
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period, allowance	63,957	63,305
Charge-offs	(13,210)	(13,475)
Recoveries	2,354	2,453
Provision	11,269	12,343
Balance, end of period, allowance	64,370	64,626
Allowance for loans and leases:
Collectively evaluated for impairment			64,157		64,203
Individually evaluated for impairment			3		5
Total	63,957	63,305	64,370	63,957	64,626
Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]
Collectively evaluated for impairment			4,775,727		4,372,758
Individually evaluated for impairment			16,710		24,043
Total			4,793,100		4,400,884
Commercial \| Receivables Acquired with Deteriorated Credit Quality
Allowance for loans and leases:
Loans acquired with deteriorated credit quality			210		418
Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]
Loans acquired with deteriorated credit quality			663		4,083
Residential
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period, allowance	22,034	19,360
Charge-offs	(135)	(246)
Recoveries	155	203
Provision	119	516
Balance, end of period, allowance	22,173	19,833
Allowance for loans and leases:
Collectively evaluated for impairment			21,819		19,451
Individually evaluated for impairment			0		0
Total	22,034	19,360	22,173	22,034	19,833
Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]
Collectively evaluated for impairment			4,913,713		4,345,522
Individually evaluated for impairment			0		0
Total			4,939,207		4,378,136
Residential \| Receivables Acquired with Deteriorated Credit Quality
Allowance for loans and leases:
Loans acquired with deteriorated credit quality			354		382
Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]
Loans acquired with deteriorated credit quality			25,494		32,614
Consumer & other, net
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period, allowance	10,976	12,178
Charge-offs	(1,656)	(1,780)
Recoveries	623	608
Provision	545	463
Balance, end of period, allowance	10,488	11,469
Allowance for loans and leases:
Collectively evaluated for impairment			10,445		11,428
Individually evaluated for impairment			0		0
Total	$ 10,976	$ 12,178	10,488	$ 10,976	11,469
Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]
Collectively evaluated for impairment			551,671		685,424
Individually evaluated for impairment			0		0
Total			552,064		685,838
Consumer & other, net \| Receivables Acquired with Deteriorated Credit Quality
Allowance for loans and leases:
Loans acquired with deteriorated credit quality			43		41
Financing Receivable, Allowance for Credit Loss, Loans And Leases [Abstract]
Loans acquired with deteriorated credit quality			$ 393		$ 414