Operating Segment Information Operating Segment Information (Tables)

12 Months Ended

Dec. 31, 2018

Operating Segment Information [Abstract]

Schedule of Segment Reporting Information, by Segment

(In millions)	Zions Bank								Amegy									CB&T
	2018		2017			2016			2018			2017			2016			2018		2017			2016
SELECTED INCOME STATEMENT DATA
Net interest income	$	699	$	648		$	622		$	519		$	482		$	460		$	538	$	481		$	434
Provision for loan losses	7		19			(22		)	(75		)	25			163			14		(5		)	(9		)
Net interest income after provision for loan losses	692		629			644			594			457			297			524		486			443
Noninterest income	150		151			149			126			118			123			82		75			67
Noninterest expense	463		436			424			338			336			326			309		299			290
Income before income taxes	$	379	$	344		$	369		$	382		$	239		$	94		$	297	$	262		$	220
SELECTED AVERAGE BALANCE SHEET DATA
Total average loans	$	12,643	$	12,481		$	12,538		$	11,358		$	11,021		$	10,595		$	10,033	$	9,539		$	9,211
Total average deposits	15,874		15,986			15,991			11,160			11,096			11,130			11,268		11,030			10,827
(In millions)	NBAZ								NSB									Vectra
	2018		2017			2016			2018			2017			2016			2018		2017			2016
SELECTED INCOME STATEMENT DATA
Net interest income	$	231	$	204		$	190		$	151		$	131		$	122		$	137	$	127		$	120
Provision for loan losses	7		(8		)	(3		)	—			(11		)	(28		)	5		1			(8		)
Net interest income after provision for loan losses	224		212			193			151			142			150			132		126			128
Noninterest income	39		40			40			41			40			39			24		25			23
Noninterest expense	153		148			144			144			139			137			105		101			97
Income before income taxes	$	110	$	104		$	89		$	48		$	43		$	52		$	51	$	50		$	54
SELECTED AVERAGE BALANCE SHEET DATA
Total average loans	$	4,608	$	4,267		$	4,086		$	2,394		$	2,357		$	2,284		$	2,924	$	2,644		$	2,469
Total average deposits	4,931		4,762			4,576			4,286			4,254			4,137			2,761		2,756			2,720

(In millions)	TCBW						Other									Consolidated Bank
	2018		2017		2016		2018			2017			2016			2018			2017		2016
SELECTED INCOME STATEMENT DATA
Net interest income	$	55	$	46	$	38	$	(100	)	$	(54	)	$	(119	)	$	2,230		$	2,065	$	1,867
Provision for loan losses	2		2		—		1			1			—			(39		)	24		93
Net interest income after provision for loan losses	53		44		38		(101		)	(55		)	(119		)	2,269			2,041		1,774
Noninterest income	5		5		5		85			90			70			552			544		516
Noninterest expense	22		20		19		144			170			148			1,678			1,649		1,585
Income (loss) before income taxes	$	36	$	29	$	24	$	(160	)	$	(135	)	$	(197	)	$	1,143		$	936	$	705
SELECTED AVERAGE BALANCE SHEET DATA
Total average loans	$	1,118	$	926	$	791	$	347		$	266		$	88		$	45,425		$	43,501	$	42,062
Total average deposits	1,092		1,107		1,007		1,811			1,209			207			53,183			52,200		50,595