Segments (Schedule Of Financial Information By Segment) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 Operating_Segments	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Number of operating segments	3us-gaap_NumberOfOperatingSegments
Net interest income	$ 620,204us-gaap_InterestIncomeExpenseNet	$ 619,372us-gaap_InterestIncomeExpenseNet	$ 639,906us-gaap_InterestIncomeExpenseNet
Provision for loan losses	(29,531)us-gaap_ProvisionForLoanAndLeaseLosses	(20,353)us-gaap_ProvisionForLoanAndLeaseLosses	(27,287)us-gaap_ProvisionForLoanAndLeaseLosses
Non-interest income	435,978us-gaap_NoninterestIncome	418,386us-gaap_NoninterestIncome	399,630us-gaap_NoninterestIncome
Investment securities gains (losses), net	14,124us-gaap_GainLossOnInvestments	(4,425)us-gaap_GainLossOnInvestments	4,828us-gaap_GainLossOnInvestments
Non-interest expense	(657,775)us-gaap_NoninterestExpense	(629,633)us-gaap_NoninterestExpense	(618,469)us-gaap_NoninterestExpense
Income before income taxes	383,000	383,347	398,608
Consumer Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	270,081	268,221	274,844
Provision for loan losses	(35,209)	(34,277)	(35,496)
Non-interest income	113,245	112,819	114,003
Investment securities gains (losses), net	0	0	0
Non-interest expense	(267,931)	(270,209)	(266,740)
Income before income taxes	80,186	76,554	86,611
Commercial Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	287,244	280,128	290,968
Provision for loan losses	559	3,772	(2,824)
Non-interest income	190,594	186,446	179,824
Investment securities gains (losses), net	0	0	0
Non-interest expense	(250,964)	(235,396)	(226,935)
Income before income taxes	227,433	234,950	241,033
Wealth Segment [Member]
Segment Reporting Information [Line Items]
Net interest income	40,128	40,185	39,498
Provision for loan losses	372	(688)	(695)
Non-interest income	128,203	117,323	108,776
Investment securities gains (losses), net	0	0	0
Non-interest expense	(98,589)	(96,530)	(90,659)
Income before income taxes	70,114	60,290	56,920
Segment Totals [Member]
Segment Reporting Information [Line Items]
Net interest income	597,453	588,534	605,310
Provision for loan losses	(34,278)	(31,193)	(39,015)
Non-interest income	432,042	416,588	402,603
Investment securities gains (losses), net	0	0	0
Non-interest expense	(617,484)	(602,135)	(584,334)
Income before income taxes	377,733	371,794	384,564
Other/Elimination [Member]
Segment Reporting Information [Line Items]
Net interest income	22,751	30,838	34,596
Provision for loan losses	4,747	10,840	11,728
Non-interest income	3,936	1,798	(2,973)
Investment securities gains (losses), net	14,124	(4,425)	4,828
Non-interest expense	(40,291)	(27,498)	(34,135)
Income before income taxes	$ 5,267	$ 11,553	$ 14,044

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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