Segments (Schedule Of Financial Information By Segment) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Net interest income		$ 203,488	$ 192,892
Provision for loan losses		(12,463)	(10,396)
Non-interest income		121,240	119,690
Investment securities gains (losses), net	[1]	(925)	5,410
Non-interest expense		(191,425)	(182,277)
Income before income taxes		119,915	125,319
Consumer Segment [Member]
Segment Reporting Information [Line Items]
Net interest income		76,897	71,021
Provision for loan losses		(11,049)	(10,373)
Non-interest income		29,171	30,216
Investment securities gains (losses), net		0	0
Non-interest expense		(73,508)	(69,919)
Income before income taxes		21,511	20,945
Commercial Segment [Member]
Segment Reporting Information [Line Items]
Net interest income		85,848	82,584
Provision for loan losses		(618)	180
Non-interest income		47,915	49,209
Investment securities gains (losses), net		0	0
Non-interest expense		(76,838)	(72,778)
Income before income taxes		56,307	59,195
Wealth Segment [Member]
Segment Reporting Information [Line Items]
Net interest income		11,676	11,445
Provision for loan losses		33	(64)
Non-interest income		44,332	42,103
Investment securities gains (losses), net		0	0
Non-interest expense		(30,892)	(31,825)
Income before income taxes		25,149	21,659
Segment Totals [Member]
Segment Reporting Information [Line Items]
Net interest income		174,421	165,050
Provision for loan losses		(11,634)	(10,257)
Non-interest income		121,418	121,528
Investment securities gains (losses), net		0	0
Non-interest expense		(181,238)	(174,522)
Income before income taxes		102,967	101,799
Other Elimination [Member]
Segment Reporting Information [Line Items]
Net interest income		29,067	27,842
Provision for loan losses		(829)	(139)
Non-interest income		(178)	(1,838)
Investment securities gains (losses), net		(925)	5,410
Non-interest expense		(10,187)	(7,755)
Income before income taxes		$ 16,948	$ 23,520

[1] Available for sale debt securities, equity securities, and other securities