Segments (Schedule Of Financial Information By Segment) (Details)	3 Months Ended		6 Months Ended				12 Months Ended
	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)		Jun. 30, 2014 USD ($)		Dec. 31, 2014
Segment Reporting Information [Line Items]
Segment Reporting Information, Intersegment Revenue	$ 0	$ 0	$ 0		$ 0
Number of operating segments			3				3
Net interest income	163,657,000	160,493,000	$ 309,795,000		313,559,000
Provision for loan losses	(6,757,000)	(7,555,000)	(11,177,000)		(17,215,000)
Non-interest income	114,092,000	108,763,000	220,518,000		211,390,000
Investment securities gains (losses), net	2,143,000	(2,558,000)	8,178,000	[1]	7,479,000	[1]
Non-interest expense	(165,320,000)	(162,553,000)	(329,017,000)		(324,515,000)
Income before income taxes	107,815,000	96,590,000	198,297,000		190,698,000
Consumer Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	66,517,000	66,440,000	132,182,000		131,968,000
Provision for loan losses	(8,572,000)	(8,312,000)	(16,895,000)		(17,510,000)
Non-interest income	30,206,000	28,825,000	56,600,000		54,632,000
Investment securities gains (losses), net	0	0	0		0
Non-interest expense	(67,587,000)	(66,366,000)	(134,250,000)		(131,320,000)
Income before income taxes	20,564,000	20,587,000	37,637,000		37,770,000
Commercial Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	73,631,000	71,301,000	144,378,000		142,387,000
Provision for loan losses	(201,000)	323,000	676,000		(60,000)
Non-interest income	49,618,000	47,533,000	97,199,000		94,637,000
Investment securities gains (losses), net	0	0	0		0
Non-interest expense	(65,714,000)	(63,048,000)	(130,317,000)		(124,681,000)
Income before income taxes	57,334,000	56,109,000	111,936,000		112,283,000
Wealth Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	10,739,000	9,991,000	21,530,000		19,902,000
Provision for loan losses	1,000	533,000	8,000		492,000
Non-interest income	34,737,000	31,507,000	68,294,000		61,502,000
Investment securities gains (losses), net	0	0	0		0
Non-interest expense	(27,004,000)	(23,991,000)	(54,287,000)		(48,773,000)
Income before income taxes	18,473,000	18,040,000	35,545,000		33,123,000
Segment Totals [Member]
Segment Reporting Information [Line Items]
Net interest income	150,887,000	147,732,000	298,090,000		294,257,000
Provision for loan losses	(8,772,000)	(7,456,000)	(16,211,000)		(17,078,000)
Non-interest income	114,561,000	107,865,000	222,093,000		210,771,000
Investment securities gains (losses), net	0	0	0		0
Non-interest expense	(160,305,000)	(153,405,000)	(318,854,000)		(304,774,000)
Income before income taxes	96,371,000	94,736,000	185,118,000		183,176,000
Other Elimination [Member]
Segment Reporting Information [Line Items]
Net interest income	12,770,000	12,761,000	11,705,000		19,302,000
Provision for loan losses	2,015,000	(99,000)	5,034,000		(137,000)
Non-interest income	(469,000)	898,000	(1,575,000)		619,000
Investment securities gains (losses), net	2,143,000	(2,558,000)	8,178,000		7,479,000
Non-interest expense	(5,015,000)	(9,148,000)	(10,163,000)		(19,741,000)
Income before income taxes	$ 11,444,000	$ 1,854,000	$ 13,179,000		$ 7,522,000

[1] Available for sale and non-marketable securities