Asset Quality (Consumer Real Estate Secured Asset Quality Indicators) (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
% of Loans	100.00%	100.00%
Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	$ 16,324	$ 16,600
Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	11,555	12,228
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	14,290	13,028
Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	$ 42,169	$ 41,856
Total home equity and residential real estate loans [Member] | New Jersey [Member] | High Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
% of Loans	17.00%	16.00%
Total home equity and residential real estate loans [Member] | Pennsylvania [Member] | High Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
% of Loans	12.00%	14.00%
Total home equity and residential real estate loans [Member] | Illinois [Member] | High Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
% of Loans	12.00%	12.00%
Total home equity and residential real estate loans [Member] | Ohio [Member] | High Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
% of Loans	9.00%	10.00%
Total home equity and residential real estate loans [Member] | Maryland [Member] | High Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
% of Loans	8.00%	6.00%
Total home equity and residential real estate loans [Member] | Florida [Member] | High Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
% of Loans	7.00%	7.00%
Total home equity and residential real estate loans [Member] | Michigan [Member] | High Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
% of Loans	5.00%	4.00%
Total home equity and residential real estate loans [Member] | North Carolina [Member] | High Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
% of Loans	4.00%	4.00%
Total home equity and residential real estate loans [Member] | All Other States Maximum [Member] | High Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
% of Loans	4.00%	4.00%
Total home equity and residential real estate loans [Member] | All Other States [Member] | High Risk [Member]
Financing Receivable, Recorded Investment [Line Items]
% of Loans	26.00%	27.00%
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	$ 131	$ 161
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	432	629
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	141	174
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	704	964
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	20	32
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	69	110
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	42	35
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	131	177
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Missing [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	1	1
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Missing [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	5	9
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Missing [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	2	2
LTV greater than or equal to 125% and updated FICO scores [Member] | FICO Score- Missing [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	8	12
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	337	394
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	958	1,190
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	306	345
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	1,601	1,929
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	55	66
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	160	211
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	78	76
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	293	353
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Missing [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	3	3
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Missing [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	10	10
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Missing [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	7	7
LTV greater than or equal to 100% to less than 125% and updated FICO scores [Member] | FICO Score- Missing [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	20	20
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	379	453
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	995	1,100
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	358	463
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	1,732	2,016
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	61	77
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	144	171
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	63	78
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	268	326
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Missing [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	2	1
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Missing [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	8	8
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Missing [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	5	6
LTV greater than or equal to 90% to less than 100% and updated FICO scores [Member] | FICO Score- Missing [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	15	15
LTV less than 90% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	14,066	14,047
LTV less than 90% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	7,958	7,913
LTV less than 90% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	12,656	11,153
LTV less than 90% and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	34,680	33,113
LTV less than 90% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	1,227	1,323
LTV less than 90% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	761	822
LTV less than 90% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	542	586
LTV less than 90% and updated FICO scores [Member] | FICO Score- Less than or equal to 660 [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	2,530	2,731
LTV less than 90% and updated FICO scores [Member] | FICO Score- Missing [Member] | Home Equity [Member] | 1st Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	42	42
LTV less than 90% and updated FICO scores [Member] | FICO Score- Missing [Member] | Home Equity [Member] | 2nd Liens [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	55	55
LTV less than 90% and updated FICO scores [Member] | FICO Score- Missing [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	90	102
LTV less than 90% and updated FICO scores [Member] | FICO Score- Missing [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	187	199
Missing LTV and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	0	1
Missing LTV and updated FICO scores [Member] | FICO Score- Greater than 660 [Member] | Total home equity and residential real estate loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans - Excluding purchased impaired and government insured or guaranteed loans	$ 0	$ 1