Segments (Schedule Of Financial Information By Segment) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)		Jun. 30, 2015 USD ($)
Segment Reporting Information [Line Items]
Segment Reporting Information, Intersegment Revenue	$ 0	$ 0	$ 0		$ 0
Number of operating segments			3		3
Net interest income	171,829,000	163,657,000	$ 335,604,000		$ 309,795,000
Provision for loan losses	(9,216,000)	(6,757,000)	(18,655,000)		(11,177,000)
Non-interest income	116,570,000	114,235,000	235,594,000		220,809,000
Investment securities gains (losses), net	(744,000)	2,143,000	(1,739,000)	[1]	8,178,000	[1]
Non-interest expense	(177,089,000)	(165,463,000)	(354,562,000)		(329,308,000)
Income before income taxes	101,350,000	107,815,000	196,242,000		198,297,000
Consumer Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	67,221,000	66,516,000	133,791,000		132,180,000
Provision for loan losses	(8,775,000)	(8,572,000)	(17,500,000)		(16,895,000)
Non-interest income	33,040,000	29,751,000	62,936,000		56,363,000
Investment securities gains (losses), net	0	0	0		0
Non-interest expense	(70,560,000)	(67,590,000)	(139,536,000)		(134,282,000)
Income before income taxes	20,926,000	20,105,000	39,691,000		37,366,000
Commercial Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	77,104,000	73,112,000	153,015,000		144,223,000
Provision for loan losses	1,468,000	(201,000)	1,487,000		676,000
Non-interest income	48,289,000	49,618,000	99,408,000		97,199,000
Investment securities gains (losses), net	0	0	0		0
Non-interest expense	(70,779,000)	(65,614,000)	(140,536,000)		(130,384,000)
Income before income taxes	56,082,000	56,915,000	113,374,000		111,714,000
Wealth Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	10,947,000	10,752,000	21,822,000		21,494,000
Provision for loan losses	(9,000)	1,000	(115,000)		8,000
Non-interest income	36,619,000	34,878,000	71,021,000		68,537,000
Investment securities gains (losses), net	0	0	0		0
Non-interest expense	(28,300,000)	(26,980,000)	(56,840,000)		(54,250,000)
Income before income taxes	19,257,000	18,651,000	35,888,000		35,789,000
Segment Totals [Member]
Segment Reporting Information [Line Items]
Net interest income	155,272,000	150,380,000	308,628,000		297,897,000
Provision for loan losses	(7,316,000)	(8,772,000)	(16,128,000)		(16,211,000)
Non-interest income	117,948,000	114,247,000	233,365,000		222,099,000
Investment securities gains (losses), net	0	0	0		0
Non-interest expense	(169,639,000)	(160,184,000)	(336,912,000)		(318,916,000)
Income before income taxes	96,265,000	95,671,000	188,953,000		184,869,000
Other Elimination [Member]
Segment Reporting Information [Line Items]
Net interest income	16,557,000	13,277,000	26,976,000		11,898,000
Provision for loan losses	(1,900,000)	2,015,000	(2,527,000)		5,034,000
Non-interest income	(1,378,000)	(12,000)	2,229,000		(1,290,000)
Investment securities gains (losses), net	(744,000)	2,143,000	(1,739,000)		8,178,000
Non-interest expense	(7,450,000)	(5,279,000)	(17,650,000)		(10,392,000)
Income before income taxes	$ 5,085,000	$ 12,144,000	$ 7,289,000		$ 13,428,000

[1] Available for sale and non-marketable securities