Segments (Schedule Of Financial Information By Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Net interest income	$ 211,634	$ 210,959	$ 415,122	$ 403,851
Provision for loan losses	(11,806)	(10,043)	(24,269)	(20,439)
Non-interest income	127,259	124,850	248,499	244,540
Investment securities gains (losses), net	(110)	(3,075)	(1,035)	2,335
Non-interest expense	(189,779)	(181,860)	(381,204)	(364,137)
Income before income taxes	137,198	140,831	257,113	266,150
Consumer Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	79,207	73,104	156,104	144,125
Provision for loan losses	(11,255)	(10,287)	(22,304)	(20,660)
Non-interest income	33,620	32,116	62,791	62,332
Investment securities gains (losses), net	0	0	0	0
Non-interest expense	(76,124)	(71,662)	(149,632)	(141,581)
Income before income taxes	25,448	23,271	46,959	44,216
Commercial Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	85,076	85,227	170,924	167,811
Provision for loan losses	(90)	308	(708)	488
Non-interest income	50,278	51,647	98,193	100,856
Investment securities gains (losses), net	0	0	0	0
Non-interest expense	(78,690)	(75,380)	(155,528)	(148,158)
Income before income taxes	56,574	61,802	112,881	120,997
Wealth Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	12,576	11,857	24,252	23,302
Provision for loan losses	(1)	16	32	(48)
Non-interest income	45,032	42,901	89,364	85,004
Investment securities gains (losses), net	0	0	0	0
Non-interest expense	(31,217)	(30,285)	(62,109)	(62,110)
Income before income taxes	26,390	24,489	51,539	46,148
Segment Totals [Member]
Segment Reporting Information [Line Items]
Net interest income	176,859	170,188	351,280	335,238
Provision for loan losses	(11,346)	(9,963)	(22,980)	(20,220)
Non-interest income	128,930	126,664	250,348	248,192
Investment securities gains (losses), net	0	0	0	0
Non-interest expense	(186,031)	(177,327)	(367,269)	(351,849)
Income before income taxes	108,412	109,562	211,379	211,361
Other Elimination [Member]
Segment Reporting Information [Line Items]
Net interest income	34,775	40,771	63,842	68,613
Provision for loan losses	(460)	(80)	(1,289)	(219)
Non-interest income	(1,671)	(1,814)	(1,849)	(3,652)
Investment securities gains (losses), net	(110)	(3,075)	(1,035)	2,335
Non-interest expense	(3,748)	(4,533)	(13,935)	(12,288)
Income before income taxes	$ 28,786	$ 31,269	$ 45,734	$ 54,789