Goodwill And Other Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Amortizing Intangible Assets

	Gross carrying amount				Accumulated amortization						Net carrying amount
(In millions)	2017		2016		2017			2016			2017		2016
Core deposit intangibles	$	167	$	167	$	(165	)	$	(159	)	$	2	$	8
Customer relationships and other intangibles	28		28		(28		)	(28		)	—		—
Total	$	195	$	195	$	(193	)	$	(187	)	$	2	$	8

Schedule Of Goodwill

(In millions)	Zions Bank		CB&T		Amegy		Consolidated Company
Balance at December 31, 2015	$	20	$	379	$	615	$	1,014
Impairment losses	—		—		—		—
Balance at December 31, 2016	20		379		615		1,014
Impairment losses	—		—		—		—
Balance at December 31, 2017	$	20	$	379	$	615	$	1,014