Credit Quality And Allowance For Credit Losses (Average Individually Evaluated Impaired Loans And Related Interest Recognized) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		$ 249	$ 256	$ 238	$ 262
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		1	1	2	2
Business loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		213	209	200	214
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		1	1	2	2
Business loans | Commercial
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		152	56	138	62
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		1	0	2	0
Business loans | Real estate construction | Commercial Real Estate business line
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period	[1]	0	17	0	18
Individually Evaluated Impaired Loans Interest Income Recognized for the Period	[1]	0	0	0	0
Business loans | Commercial mortgage
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		56	134	59	132
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	1	0	2
Business loans | Commercial mortgage | Commercial Real Estate business line
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period	[1]	16	63	17	62
Individually Evaluated Impaired Loans Interest Income Recognized for the Period	[1]	0	0	0	0
Business loans | Commercial mortgage | Other business lines
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period	[2]	40	71	42	70
Individually Evaluated Impaired Loans Interest Income Recognized for the Period	[2]	0	1	0	2
Business loans | International
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		5	2	3	2
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Retail loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		36	47	38	48
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Retail loans | Residential mortgage
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		19	31	21	32
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Retail loans | Consumer
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		17	16	17	16
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Retail loans | Consumer | Home equity
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		12	12	12	12
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Retail loans | Consumer | Other consumer
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		5	4	5	4
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		$ 0	$ 0	$ 0	$ 0

[1] Primarily loans to real estate developers.

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