Credit Quality And Allowance For Credit Losses (Troubled Debt Restructurings By Type Of Modification) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	$ 1		$ 27		$ 12		$ 68
Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[1]	16	[1]	10	[1]	47	[1]
Extension Term, Minimum Period					90 days		90 days
Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	1		2		2		2
AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period			9	[2]			19	[2]
Business loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0		23		10		62
Business loans | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[1]	14	[1]	10	[1]	43	[1]
Business loans | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0		0		0		0
Business loans | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period			9	[2]			19	[2]
Business loans | Commercial
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0		13		1		20
Business loans | Commercial | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[1]	4	[1]	1	[1]	11	[1]
Business loans | Commercial | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0		0		0		0
Business loans | Commercial | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period			9	[2]			9	[2]
Business loans | Commercial mortgage
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0		10		8		42
Business loans | Commercial mortgage | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[1]	10	[1]	8	[1]	32	[1]
Business loans | Commercial mortgage | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0		0		0		0
Business loans | Commercial mortgage | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period			0	[2]			10	[2]
Business loans | Commercial mortgage | Commercial Real Estate business line
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[3]	5	[3]	0	[3]	21	[3]
Business loans | Commercial mortgage | Commercial Real Estate business line | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[1],[3]	5	[1],[3]	0	[1],[3]	21	[1],[3]
Business loans | Commercial mortgage | Commercial Real Estate business line | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[3]	0	[3]	0	[3]	0	[3]
Business loans | Commercial mortgage | Commercial Real Estate business line | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period			0	[2],[3]			0	[2],[3]
Business loans | Commercial mortgage | Other business lines
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[4]	5	[4]	8	[4]	21	[4]
Business loans | Commercial mortgage | Other business lines | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[1],[4]	5	[1],[4]	8	[1],[4]	11	[1],[4]
Business loans | Commercial mortgage | Other business lines | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[4]	0	[4]	0	[4]	0	[4]
Business loans | Commercial mortgage | Other business lines | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period			0	[2],[4]			10	[2],[4]
Business loans | International
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period					1		0
Business loans | International | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period					1	[1]	0	[1]
Business loans | International | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period					0		0
Business loans | International | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period							0	[2]
Retail loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	1		4		2		6
Retail loans | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[1]	2	[1]	0	[1]	4	[1]
Retail loans | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	1		2		2		2
Retail loans | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period			0	[2]			0	[2]
Retail loans | Residential mortgage
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0		2		0		2
Retail loans | Residential mortgage | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[1]	1	[1],[5]	0	[1]	1	[1],[5]
Retail loans | Residential mortgage | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0		1		0		1
Retail loans | Residential mortgage | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period			0	[2]			0	[2]
Retail loans | Consumer
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period					2		4
Retail loans | Consumer | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period					0	[1]	3	[1]
Retail loans | Consumer | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period					2		1
Retail loans | Consumer | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period							0	[2]
Retail loans | Consumer | Home equity
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	1		2		2		3
Retail loans | Consumer | Home equity | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	0	[1]	1	[1],[5]	0	[1]	2	[1],[5]
Retail loans | Consumer | Home equity | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	1		1		2		1
Retail loans | Consumer | Home equity | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period			0	[2]			0	[2]
Retail loans | Consumer | Other consumer
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period					0		1
Retail loans | Consumer | Other consumer | Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period					0	[1]	1	[1],[5]
Retail loans | Consumer | Other consumer | Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period					0		0
Retail loans | Consumer | Other consumer | AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period							$ 0	[2]

[1] Primarily represents loan balances where terms were extended 90 days or more at or above contractual interest rates.

[2] Loan restructurings whereby the original loan is restructured into two notes: an "A" note, which generally reflects the portion of the modified loan which is expected to be collected; and a "B" note, which is either fully charged off or exchanged for an equity interest.

[3] Primarily loans to real estate developers.

[4] Primarily loans secured by owner-occupied real estate.

[5] Includes bankruptcy loans for which the court has discharged the borrower's obligation and the borrower has not reaffirmed the debt.