Loans And Allowance For Credit Losses (Summary Of Loans In The Personal Banking Portfolio Percentage Of Balances Outstanding by FICO Score ) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Loans And Allowance For Loan Losses [Line Items]
Credit Quality Personal Real Estate Loans Excluded	$ 167.7	$ 168.9
Consumer Healthcare Loans Excluded	$ 225.2	$ 211.3
Credit quality personal banking loan table percentage loans excluded	7.00%
Personal Real Estate Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Personal Real Estate Loan [Member] | Under 600
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	2.30%	2.00%
Personal Real Estate Loan [Member] | 600 - 659
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	2.30%	2.30%
Personal Real Estate Loan [Member] | 660 - 719
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	7.80%	8.50%
Personal Real Estate Loan [Member] | 720 - 779
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	20.70%	21.90%
Personal Real Estate Loan [Member] | 780 and over
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	66.90%	65.30%
Consumer Loan [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Consumer Loan [Member] | Under 600
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	2.40%	2.50%
Consumer Loan [Member] | 600 - 659
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	3.90%	4.30%
Consumer Loan [Member] | 660 - 719
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	13.40%	12.90%
Consumer Loan [Member] | 720 - 779
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	22.30%	28.20%
Consumer Loan [Member] | 780 and over
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	58.00%	52.10%
Revolving home equity
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Revolving home equity | Under 600
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	2.00%	1.90%
Revolving home equity | 600 - 659
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	3.10%	3.30%
Revolving home equity | 660 - 719
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	10.30%	10.90%
Revolving home equity | 720 - 779
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	23.90%	22.40%
Revolving home equity | 780 and over
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	60.70%	61.50%
Credit Card Receivable [Member]
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	100.00%	100.00%
Credit Card Receivable [Member] | Under 600
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	5.00%	4.70%
Credit Card Receivable [Member] | 600 - 659
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	12.10%	12.10%
Credit Card Receivable [Member] | 660 - 719
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	29.00%	29.20%
Credit Card Receivable [Member] | 720 - 779
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	26.70%	27.00%
Credit Card Receivable [Member] | 780 and over
Loans And Allowance For Loan Losses [Line Items]
Percentage of Loan Category	27.20%	27.00%