Residential Mortgage Servicing Rights (Schedule Of Information Relates To Serviced Loan Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Transfers and Servicing [Abstract]
Balance of loans serviced for others	$ 11,874,910umpq_BalanceOfLoansServicedForOthers	$ 11,590,310umpq_BalanceOfLoansServicedForOthers
MSR as a percentage of serviced loans	0.98%	1.01%

Mortgage servicing rights, percentage of serviced loans

No definition available.

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Period Type:	duration