Segments (Schedule Of Financial Information By Segment) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Net interest income		$ 192,892	$ 178,273
Provision for loan losses		(10,396)	(11,128)
Non-interest income		119,690	109,613
Investment securities gains (losses), net	[1]	5,410	(772)
Non-interest expense		(182,277)	(179,377)
Income before income taxes		125,319	96,609
Consumer Segment [Member]
Segment Reporting Information [Line Items]
Net interest income		71,437	67,354
Provision for loan losses		(10,515)	(9,662)
Non-interest income		30,216	27,163
Investment securities gains (losses), net		0	0
Non-interest expense		(70,171)	(67,417)
Income before income taxes		20,967	17,438
Commercial Segment [Member]
Segment Reporting Information [Line Items]
Net interest income		82,095	79,870
Provision for loan losses		180	513
Non-interest income		49,211	44,910
Investment securities gains (losses), net		0	0
Non-interest expense		(72,798)	(70,365)
Income before income taxes		58,688	54,928
Wealth Segment [Member]
Segment Reporting Information [Line Items]
Net interest income		11,445	11,844
Provision for loan losses		(64)	(23)
Non-interest income		42,101	37,706
Investment securities gains (losses), net		0	0
Non-interest expense		(31,859)	(30,319)
Income before income taxes		21,623	19,208
Segment Totals [Member]
Segment Reporting Information [Line Items]
Net interest income		164,977	159,068
Provision for loan losses		(10,399)	(9,172)
Non-interest income		121,528	109,779
Investment securities gains (losses), net		0	0
Non-interest expense		(174,828)	(168,101)
Income before income taxes		101,278	91,574
Other Elimination [Member]
Segment Reporting Information [Line Items]
Net interest income		27,915	19,205
Provision for loan losses		3	(1,956)
Non-interest income		(1,838)	(166)
Investment securities gains (losses), net		5,410	(772)
Non-interest expense		(7,449)	(11,276)
Income before income taxes		$ 24,041	$ 5,035

[1] Available for sale and non-marketable securities