Credit Quality And Allowance For Credit Losses (Individually Evaluated Impaired Loans) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010
Total individually evaluated impaired loans	$ 771		$ 974
Unpaid principal balance	1,078		1,477
Related allowance for loan losses	153		197
Business Loans [Member]
Total individually evaluated impaired loans	719		927
Unpaid principal balance	1,014		1,422
Related allowance for loan losses	149		192
Business Loans [Member] | Commercial Loan [Member]
Total individually evaluated impaired loans	246		246
Unpaid principal balance	348		398
Related allowance for loan losses	57		55
Business Loans [Member] | Real Estate Construction [Member]
Total individually evaluated impaired loans	107
Unpaid principal balance	153
Related allowance for loan losses	19
Business Loans [Member] | Real Estate Construction [Member] | Commercial Real Estate Business Line [Member]
Total individually evaluated impaired loans	102	[1]	249	[1]
Unpaid principal balance	146	[1]	400	[1]
Related allowance for loan losses	18	[1]	51	[1]
Business Loans [Member] | Real Estate Construction [Member] | Other Business Lines [Member]
Total individually evaluated impaired loans	5	[2]
Unpaid principal balance	7	[2]
Related allowance for loan losses	1	[2]
Business Loans [Member] | Commercial Mortgage [Member]
Total individually evaluated impaired loans	355		423
Unpaid principal balance	497		607
Related allowance for loan losses	70		84
Business Loans [Member] | Commercial Mortgage [Member] | Commercial Real Estate Business Line [Member]
Total individually evaluated impaired loans	148	[1]	178	[1]
Unpaid principal balance	198	[1]	282	[1]
Related allowance for loan losses	34	[1]	35	[1]
Business Loans [Member] | Commercial Mortgage [Member] | Other Business Lines [Member]
Total individually evaluated impaired loans	207	[2]	245	[2]
Unpaid principal balance	299	[2]	325	[2]
Related allowance for loan losses	36	[2]	49	[2]
Business Loans [Member] | Lease Financing Loan [Member]
Total individually evaluated impaired loans	3		7
Unpaid principal balance	6		15
Related allowance for loan losses	1		1
Business Loans [Member] | International Loan [Member]
Total individually evaluated impaired loans	8		2
Unpaid principal balance	10		2
Related allowance for loan losses	2		1
Retail Loans [Member]
Total individually evaluated impaired loans	52		47
Unpaid principal balance	64		55
Related allowance for loan losses	4		5
Retail Loans [Member] | Residential Mortgage Loan [Member]
Total individually evaluated impaired loans	46		37
Unpaid principal balance	51		41
Related allowance for loan losses	3		3
Retail Loans [Member] | Consumer Loans [Member]
Total individually evaluated impaired loans	6
Unpaid principal balance	13
Related allowance for loan losses	1
Retail Loans [Member] | Consumer Loans [Member] | Home Equity [Member]
Total individually evaluated impaired loans	1
Unpaid principal balance	1
Related allowance for loan losses	0
Retail Loans [Member] | Consumer Loans [Member] | Other Consumer [Member]
Total individually evaluated impaired loans	5		10
Unpaid principal balance	12		14
Related allowance for loan losses	1		2
Impaired Financing Receivable, Related Allowance [Member]
Total individually evaluated impaired loans	747		957
Impaired Financing Receivable, Related Allowance [Member] | Business Loans [Member]
Total individually evaluated impaired loans	711		918
Impaired Financing Receivable, Related Allowance [Member] | Business Loans [Member] | Commercial Loan [Member]
Total individually evaluated impaired loans	244		237
Impaired Financing Receivable, Related Allowance [Member] | Business Loans [Member] | Real Estate Construction [Member]
Total individually evaluated impaired loans	107
Impaired Financing Receivable, Related Allowance [Member] | Business Loans [Member] | Real Estate Construction [Member] | Commercial Real Estate Business Line [Member]
Total individually evaluated impaired loans	102	[1]	249	[1]
Impaired Financing Receivable, Related Allowance [Member] | Business Loans [Member] | Real Estate Construction [Member] | Other Business Lines [Member]
Total individually evaluated impaired loans	5	[2]
Impaired Financing Receivable, Related Allowance [Member] | Business Loans [Member] | Commercial Mortgage [Member]
Total individually evaluated impaired loans	349		423
Impaired Financing Receivable, Related Allowance [Member] | Business Loans [Member] | Commercial Mortgage [Member] | Commercial Real Estate Business Line [Member]
Total individually evaluated impaired loans	148	[1]	178	[1]
Impaired Financing Receivable, Related Allowance [Member] | Business Loans [Member] | Commercial Mortgage [Member] | Other Business Lines [Member]
Total individually evaluated impaired loans	201	[2]	245	[2]
Impaired Financing Receivable, Related Allowance [Member] | Business Loans [Member] | Lease Financing Loan [Member]
Total individually evaluated impaired loans	3		7
Impaired Financing Receivable, Related Allowance [Member] | Business Loans [Member] | International Loan [Member]
Total individually evaluated impaired loans	8		2
Impaired Financing Receivable, Related Allowance [Member] | Retail Loans [Member]
Total individually evaluated impaired loans	36		39
Impaired Financing Receivable, Related Allowance [Member] | Retail Loans [Member] | Residential Mortgage Loan [Member]
Total individually evaluated impaired loans	30		29
Impaired Financing Receivable, Related Allowance [Member] | Retail Loans [Member] | Consumer Loans [Member]
Total individually evaluated impaired loans	6
Impaired Financing Receivable, Related Allowance [Member] | Retail Loans [Member] | Consumer Loans [Member] | Home Equity [Member]
Total individually evaluated impaired loans	1
Impaired Financing Receivable, Related Allowance [Member] | Retail Loans [Member] | Consumer Loans [Member] | Other Consumer [Member]
Total individually evaluated impaired loans	5		10
Impaired Financing Receivable, No Related Allowance [Member]
Total individually evaluated impaired loans	24		17
Impaired Financing Receivable, No Related Allowance [Member] | Business Loans [Member]
Total individually evaluated impaired loans	8		9
Impaired Financing Receivable, No Related Allowance [Member] | Business Loans [Member] | Commercial Loan [Member]
Total individually evaluated impaired loans	2		9
Impaired Financing Receivable, No Related Allowance [Member] | Business Loans [Member] | Real Estate Construction [Member]
Total individually evaluated impaired loans	0
Impaired Financing Receivable, No Related Allowance [Member] | Business Loans [Member] | Real Estate Construction [Member] | Commercial Real Estate Business Line [Member]
Total individually evaluated impaired loans	0	[1]	0	[1]
Impaired Financing Receivable, No Related Allowance [Member] | Business Loans [Member] | Real Estate Construction [Member] | Other Business Lines [Member]
Total individually evaluated impaired loans	0	[2]
Impaired Financing Receivable, No Related Allowance [Member] | Business Loans [Member] | Commercial Mortgage [Member]
Total individually evaluated impaired loans	6		0
Impaired Financing Receivable, No Related Allowance [Member] | Business Loans [Member] | Commercial Mortgage [Member] | Commercial Real Estate Business Line [Member]
Total individually evaluated impaired loans	0	[1]	0	[1]
Impaired Financing Receivable, No Related Allowance [Member] | Business Loans [Member] | Commercial Mortgage [Member] | Other Business Lines [Member]
Total individually evaluated impaired loans	6	[2]	0	[2]
Impaired Financing Receivable, No Related Allowance [Member] | Business Loans [Member] | Lease Financing Loan [Member]
Total individually evaluated impaired loans	0		0
Impaired Financing Receivable, No Related Allowance [Member] | Business Loans [Member] | International Loan [Member]
Total individually evaluated impaired loans	0		0
Impaired Financing Receivable, No Related Allowance [Member] | Retail Loans [Member]
Total individually evaluated impaired loans	16		8
Impaired Financing Receivable, No Related Allowance [Member] | Retail Loans [Member] | Residential Mortgage Loan [Member]
Total individually evaluated impaired loans	16		8
Impaired Financing Receivable, No Related Allowance [Member] | Retail Loans [Member] | Consumer Loans [Member]
Total individually evaluated impaired loans	0
Impaired Financing Receivable, No Related Allowance [Member] | Retail Loans [Member] | Consumer Loans [Member] | Home Equity [Member]
Total individually evaluated impaired loans	0
Impaired Financing Receivable, No Related Allowance [Member] | Retail Loans [Member] | Consumer Loans [Member] | Other Consumer [Member]
Total individually evaluated impaired loans	$ 0		$ 0

[1] Primarily loans to real estate investors and developers.

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