Parent Company Financial Statements (Schedule Of Condensed Balance Sheets) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Other assets	$ 434,201	$ 268,376
Total assets	28,846,809	26,939,781	$ 25,680,447
Other liabilities	297,782	281,474
Junior subordinated debentures, at fair value	274,812	300,870
Junior subordinated debentures, at amortized cost	88,496	88,724
Total liabilities	24,532,894	22,883,339
Shareholders' equity	4,313,915	4,056,442
Total liabilities and shareholders' equity	28,846,809	26,939,781
Umpqua Holdings Corporation
Condensed Financial Statements, Captions [Line Items]
Non-interest bearing deposits with subsidiary bank	130,368	116,245
Investments in Bank subsidiary	4,590,888	4,360,983
Investments in Nonbank subsidiaries	29,126	28,330
Other assets	518	8,478
Total assets	4,750,900	4,514,036
Payable to bank subsidiary	91	278
Other liabilities	73,586	67,722
Junior subordinated debentures, at fair value	274,812	300,870
Junior subordinated debentures, at amortized cost	88,496	88,724
Total liabilities	436,985	457,594
Shareholders' equity	4,313,915	4,056,442
Total liabilities and shareholders' equity	$ 4,750,900	$ 4,514,036