Residential Mortgage Servicing Rights (Schedule Of Information Relates To Serviced Loan Portfolio) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Transfers and Servicing [Abstract]
Balance of loans serviced for others	$ 12,533,045	$ 12,276,943
MSR as a percentage of serviced loans	0.75%	0.94%

Mortgage servicing rights, percentage of serviced loans

No definition available.

Name:	umpq_MortgageServicingRightsPercentageOfServicedLoans
Namespace Prefix:	umpq_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant