Goodwill And Other Intangible Assets (Schedule Of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 1,014,129	$ 1,015,129
Impairment losses	0
Adjustment		(1,000)
Goodwill, Ending Balance	1,014,129	1,014,129
Zions Bank [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	19,514	19,514
Impairment losses	0
Adjustment		0
Goodwill, Ending Balance	19,514	19,514
CB&T [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	379,024	379,024
Impairment losses	0
Adjustment		0
Goodwill, Ending Balance	379,024	379,024
Amegy [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	615,591	615,591
Impairment losses	0
Adjustment		0
Goodwill, Ending Balance	615,591	615,591
Other (Including ABS CDOs) [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	0	1,000
Impairment losses	0
Adjustment		(1,000)
Goodwill, Ending Balance	$ 0	$ 0