Earnings Per Common Share (Computation Of Basic And Diluted Earnings (Loss) Per Common Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				6 Months Ended				12 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013		Dec. 31, 2013
NUMERATORS:
Net income	$ 17,221		$ 26,253		$ 35,985		$ 49,614		$ 98,361
Dividends and undistributed earnings allocated to participating securities	83		197	[1]	196	[1]	380	[1]
Net earnings available to common shareholders	$ 17,138		$ 26,056		$ 35,789		$ 49,234
DENOMINATORS:
Weighted average number of common shares outstanding - basic	196,312		111,954		154,473		111,946
Effect of potentially dilutive common shares	1,326	[2]	191	[2]	803	[2]	187	[2]
Weighted average number of common shares outstanding - diluted	197,638		112,145		155,276		112,133
EARNINGS PER COMMON SHARE:
Basic (in usd per share)	$ 0.09		$ 0.23		$ 0.23		$ 0.44
Diluted (in usd per share)	$ 0.09		$ 0.23		$ 0.23		$ 0.44

[1] Represents dividends paid and undistributed earnings allocated to nonvested restricted stock awards.

[2] Represents the effect of the assumed exercise of stock options, vesting of non-participating restricted shares, and vesting of restricted stock units and warrants that were converted into warrants exercisable for Umpqua common shares in connection with the Sterling acquisition, based on the treasury stock method.