Segments (Schedule Of Financial Information By Segment) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) Operating_Segments	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| Operating_Segments	3
Net interest income	$ 823,825	$ 733,679	$ 680,049
Provision for loan losses	(42,694)	(45,244)	(36,318)
Non-interest income	501,341	461,263	446,556
Investment securities gains (losses), net	(488)	25,051	(53)
Non-interest expense	(737,821)	(744,343)	(689,229)
Income before income taxes	544,163	430,406	401,005
Consumer Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	296,228	279,031	268,654
Provision for loan losses	(41,280)	(41,829)	(36,042)
Non-interest income	126,253	121,362	116,185
Investment securities gains (losses), net	0	0	0
Non-interest expense	(287,473)	(275,734)	(266,258)
Income before income taxes	93,728	82,830	82,539
Commercial Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	345,221	329,087	311,704
Provision for loan losses	(1,134)	205	4,378
Non-interest income	202,527	184,577	187,350
Investment securities gains (losses), net	0	0	0
Non-interest expense	(297,847)	(281,845)	(272,398)
Income before income taxes	248,767	232,024	231,034
Wealth Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	46,946	47,264	44,113
Provision for loan losses	32	(41)	(122)
Non-interest income	173,026	158,175	144,661
Investment securities gains (losses), net	0	0	0
Non-interest expense	(123,576)	(120,461)	(113,888)
Income before income taxes	96,428	84,937	74,764
Segment Totals [Member]
Segment Reporting Information [Line Items]
Net interest income	688,395	655,382	624,471
Provision for loan losses	(42,382)	(41,665)	(31,786)
Non-interest income	501,806	464,114	448,196
Investment securities gains (losses), net	0	0	0
Non-interest expense	(708,896)	(678,040)	(652,544)
Income before income taxes	438,923	399,791	388,337
Other/Elimination [Member]
Segment Reporting Information [Line Items]
Net interest income	135,430	78,297	55,578
Provision for loan losses	(312)	(3,579)	(4,532)
Non-interest income	(465)	(2,851)	(1,640)
Investment securities gains (losses), net	(488)	25,051	(53)
Non-interest expense	(28,925)	(66,303)	(36,685)
Income before income taxes	$ 105,240	$ 30,615	$ 12,668

Amount of realized and unrealized gain (loss) on investment.

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