Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2021	Oct. 31, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-34624
Entity Registrant Name	Umpqua Holdings Corporation
Entity Incorporation, State or Country Code	OR
Entity Tax Identification Number	93-1261319
Entity Address, Address Line One	One SW Columbia Street
Entity Address, Address Line Two	Suite 1200
Entity Address, City or Town	Portland
Entity Address, State or Province	OR
Entity Address, Postal Zip Code	97204
City Area Code	503
Local Phone Number	727-4100
Title of 12(b) Security	Common Stock
Trading Symbol	UMPQ
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		216,621,803
Entity Central Index Key	0001077771
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false