Segments (Schedule Of Financial Information By Segment) (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Segment Reporting Information, Intersegment Revenue	$ 0us-gaap_Revenues	$ 0us-gaap_Revenues
Number of operating segments	3us-gaap_NumberOfOperatingSegments	3us-gaap_NumberOfOperatingSegments
Net interest income	146,138,000us-gaap_InterestIncomeExpenseNet	153,066,000us-gaap_InterestIncomeExpenseNet
Provision for loan losses	(4,420,000)us-gaap_ProvisionForLoanAndLeaseLosses	(9,660,000)us-gaap_ProvisionForLoanAndLeaseLosses
Non-interest income	106,426,000us-gaap_NoninterestIncome	102,627,000us-gaap_NoninterestIncome
Investment securities gains (losses), net	6,035,000us-gaap_GainLossOnInvestments	10,037,000us-gaap_GainLossOnInvestments
Non-interest expense	(163,697,000)us-gaap_NoninterestExpense	(161,962,000)us-gaap_NoninterestExpense
Income before income taxes	90,482,000	94,108,000
Consumer Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	65,665,000	65,528,000
Provision for loan losses	(8,323,000)	(9,198,000)
Non-interest income	26,394,000	25,807,000
Investment securities gains (losses), net	0	0
Non-interest expense	(66,663,000)	(64,954,000)
Income before income taxes	17,073,000	17,183,000
Commercial Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	70,747,000	71,086,000
Provision for loan losses	877,000	(383,000)
Non-interest income	47,581,000	47,104,000
Investment securities gains (losses), net	0	0
Non-interest expense	(64,603,000)	(61,633,000)
Income before income taxes	54,602,000	56,174,000
Wealth Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	10,791,000	9,911,000
Provision for loan losses	7,000	(41,000)
Non-interest income	33,557,000	29,995,000
Investment securities gains (losses), net	0	0
Non-interest expense	(27,283,000)	(24,782,000)
Income before income taxes	17,072,000	15,083,000
Segment Totals [Member]
Segment Reporting Information [Line Items]
Net interest income	147,203,000	146,525,000
Provision for loan losses	(7,439,000)	(9,622,000)
Non-interest income	107,532,000	102,906,000
Investment securities gains (losses), net	0	0
Non-interest expense	(158,549,000)	(151,369,000)
Income before income taxes	88,747,000	88,440,000
Other Elimination [Member]
Segment Reporting Information [Line Items]
Net interest income	(1,065,000)	6,541,000
Provision for loan losses	3,019,000	(38,000)
Non-interest income	(1,106,000)	(279,000)
Investment securities gains (losses), net	6,035,000	10,037,000
Non-interest expense	(5,148,000)	(10,593,000)
Income before income taxes	$ 1,735,000	$ 5,668,000

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

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The net amount of operating interest income (expense).

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Amount of expense related to estimated loss from loan and lease transactions.

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