Asset Quality and Allowances for Loan and Lease Losses and Unfunded Loan Commitments and Letters Of Credit (TDR charge off narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011		Sep. 30, 2011
Financing Receivable, Modifications [Line Items]
Number of Loans	5,836	[1]	21,348	[1]
Commercial [Member] | Charged Off Troubled Debt Restructurings [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	1		10
Amount charged off	$ 1		$ 25
Commercial Real Estate [Member] | Charged Off Troubled Debt Restructurings [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	3		14
Amount charged off	5		19
Home Equity [Member] | Charged Off Troubled Debt Restructurings [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	104		173
Amount charged off	5		10
Credit Card [Member] | Charged Off Troubled Debt Restructurings [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans	102		1,223
Amount charged off	$ 1		$ 9

[1] Impact of partial charge offs at TDR date are included in this table.