Parent Company Financial Statements (Schedule Of Condensed Balance Sheets) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Condensed Financial Statements, Captions [Line Items]
Other assets	$ 665,740	$ 399,800
Total assets	52,173,596	31,848,639
Other liabilities	814,512	585,111
Junior subordinated debentures, at fair value	316,440	323,639
Junior and other subordinated debentures, at amortized cost	107,895	87,813
Total liabilities	47,178,562	29,368,813
Shareholders' equity	4,995,034	2,479,826
Total liabilities and shareholders' equity	52,173,596	31,848,639
Umpqua Holdings Corporation
Condensed Financial Statements, Captions [Line Items]
Non-interest-bearing deposits with subsidiary bank	45,895	143,130
Investments in Bank subsidiary	5,367,612	2,744,195
Investments in Nonbank subsidiaries	18,951	16,932
Other assets	7,781	4,048
Total assets	5,440,239	2,908,305
Payable to bank subsidiary	444	128
Other liabilities	20,426	16,899
Junior subordinated debentures, at fair value	316,440	323,639
Junior and other subordinated debentures, at amortized cost	107,895	87,813
Total liabilities	445,205	428,479
Shareholders' equity	4,995,034	2,479,826
Total liabilities and shareholders' equity	$ 5,440,239	$ 2,908,305