Loans And Allowance For Credit Losses (Summary Of Loans In The Personal Banking Portfolio Percentage Of Balances Outstanding ) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Loans And Allowance For Loan Losses [Line Items]
Credit Quality Personal Real Estate Loans Excluded	$ 183.4	$ 185.6
Consumer Healthcare Loans Excluded	$ 181.8	$ 186.6
Credit quality personal banking loan table percentage loans excluded	7.00%
Real estate - personal
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Real estate - personal | Under 600
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	0.90%	1.00%
Real estate - personal | 600 - 659
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	2.50%	2.40%
Real estate - personal | 660 - 719
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	7.20%	7.40%
Real estate - personal | 720 - 779
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	26.60%	25.20%
Real estate - personal | 780 and over
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	62.80%	64.00%
Consumer
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Consumer | Under 600
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	1.90%	1.90%
Consumer | 600 - 659
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	3.90%	3.90%
Consumer | 660 - 719
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	13.50%	13.80%
Consumer | 720 - 779
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	24.90%	25.30%
Consumer | 780 and over
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	55.80%	55.10%
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
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	0.90%	0.90%
Revolving Home Equity [Member] | 600 - 659
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	2.60%	2.60%
Revolving Home Equity [Member] | 660 - 719
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	10.10%	9.40%
Revolving Home Equity [Member] | 720 - 779
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	21.70%	20.40%
Revolving Home Equity [Member] | 780 and over
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	64.70%	66.70%
Consumer credit card
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Consumer credit card | Under 600
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	3.40%	3.40%
Consumer credit card | 600 - 659
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	11.30%	11.30%
Consumer credit card | 660 - 719
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	31.00%	29.90%
Consumer credit card | 720 - 779
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	28.00%	28.20%
Consumer credit card | 780 and over
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	26.30%	27.20%