Loans And Allowance For Loan Losses (Summary Of Loans In The Personal Banking Portfolio Percentage Of Balances Outstanding ) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Loans And Allowance For Loan Losses [Abstract]
Credit Quality Personal Real Estate Loans Excluded	$ 237.2	$ 257.8
Credit quality personal banking loan table percentage loans excluded	6.00%
Real Estate - Personal [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Real Estate - Personal [Member] | Under 600 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	1.30%	1.50%
Real Estate - Personal [Member] | 600 - 659 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	2.60%	3.00%
Real Estate - Personal [Member] | 660 - 719 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	10.40%	9.10%
Real Estate - Personal [Member] | 720 - 779 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	25.40%	25.00%
Real Estate - Personal [Member] | 780 and over [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	60.30%	61.40%
Consumer [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Consumer [Member] | Under 600 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	3.40%	4.50%
Consumer [Member] | 600 - 659 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	6.40%	9.70%
Consumer [Member] | 660 - 719 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	19.70%	21.80%
Consumer [Member] | 720 - 779 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	26.30%	26.40%
Consumer [Member] | 780 and over [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	44.20%	37.60%
Revolving Home Equity [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Revolving Home Equity [Member] | Under 600 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	1.00%	1.50%
Revolving Home Equity [Member] | 600 - 659 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	1.80%	3.90%
Revolving Home Equity [Member] | 660 - 719 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	9.70%	13.60%
Revolving Home Equity [Member] | 720 - 779 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	21.10%	28.40%
Revolving Home Equity [Member] | 780 and over [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	66.40%	52.60%
Consumer Credit Card [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Consumer Credit Card [Member] | Under 600 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	4.90%	3.90%
Consumer Credit Card [Member] | 600 - 659 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	15.50%	12.00%
Consumer Credit Card [Member] | 660 - 719 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	34.90%	31.70%
Consumer Credit Card [Member] | 720 - 779 [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	25.10%	27.90%
Consumer Credit Card [Member] | 780 and over [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	19.60%	24.50%