Parent Company Financial Statements (Schedule Of Condensed Statements Of Cash Flows) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Financial Statements, Captions [Line Items]
Net income	$ 420,300	$ (1,523,420)	$ 354,095
Depreciation, amortization and accretion	31,498	37,474	43,286
Net (increase) decrease in other assets	153,148	(209,822)	(137,981)
Net increase in other liabilities	(9,376)	9,153	(367)
Net cash provided by (used in) operating activities	662,723	93,774	(80,479)
Net cash received from sale of Umpqua Investments, Inc.	10,781	0	0
Net cash used in investing activities	(1,534,275)	(960,111)	(550,151)
Dividends paid on common stock	(183,734)	(184,978)	(185,101)
Repurchases and retirement of common stock	(80,690)	(8,655)	(7,268)
Net cash provided by financing activities	1,059,992	2,076,762	1,370,749
Net increase in cash and cash equivalents	188,440	1,210,425	740,119
Cash and cash equivalents, beginning of period	2,573,181	1,362,756	622,637
Cash and cash equivalents, end of period	2,761,621	2,573,181	1,362,756
Umpqua Holdings Corporation
Condensed Financial Statements, Captions [Line Items]
Net income	420,300	(1,523,420)	354,095
Gain on sale of Umpqua Investments, Inc.	(4,444)	0	0
Equity in undistributed (earnings) losses of subsidiaries	(23,876)	1,722,081	(155,683)
Depreciation, amortization and accretion	(228)	(228)	(228)
Net (increase) decrease in other assets	(1,001)	(5)	7,960
Net increase in other liabilities	2,589	1,262	79
Net cash provided by (used in) operating activities	393,340	199,690	206,223
Net (increase) decrease in advances to subsidiaries	(313)	315	69
Net cash received from sale of Umpqua Investments, Inc.	10,781	0	0
Net cash used in investing activities	10,468	315	69
Net increase in advances from subsidiaries	409	5	179
Dividends paid on common stock	(183,734)	(184,978)	(185,101)
Repurchases and retirement of common stock	(80,690)	(8,655)	(7,268)
Net proceeds from issuance of common stock	34	0	21
Net cash provided by financing activities	(263,981)	(193,628)	(192,169)
Net increase in cash and cash equivalents	139,827	6,377	14,123
Cash and cash equivalents, beginning of period	136,745	130,368	116,245
Cash and cash equivalents, end of period	$ 276,572	$ 136,745	$ 130,368