Asset Quality (Credit Card and Other Consumer Loan Classes Asset Quality Indicators) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013		Dec. 31, 2012		Jun. 30, 2012
Total Loans	$ 189,775	[1],[2]	$ 185,856	[1],[2]	$ 180,425
Credit Card [Member]
Total Loans	4,135		4,303
Weighted-average updated FICO score	727		726
Higher Risk Loans	33		36
Other Consumer [Member]
Total Loans	21,177		21,451
Weighted-average updated FICO score	741		739
FICO score greater than 719 | Credit Card [Member]
Total Loans	2,178		2,247
% of Total Loans Using FICO Credit Metric	53.00%		52.00%
FICO score greater than 719 | Other Consumer [Member]
Total Loans	7,709		7,006
% of Total Loans Using FICO Credit Metric	63.00%		60.00%
FICO score of 650 to 719 [Member] | Credit Card [Member]
Total Loans	1,153		1,169
% of Total Loans Using FICO Credit Metric	28.00%		27.00%
FICO score of 650 to 719 [Member] | Other Consumer [Member]
Total Loans	3,225		2,896
% of Total Loans Using FICO Credit Metric	25.00%		25.00%
FICO score of 620 to 649 [Member] | Credit Card [Member]
Total Loans	180		188
% of Total Loans Using FICO Credit Metric	4.00%		5.00%
FICO score of 620 to 649 [Member] | Other Consumer [Member]
Total Loans	467		459
% of Total Loans Using FICO Credit Metric	4.00%		4.00%
FICO score of less Than 620 [Member] | Credit Card [Member]
Total Loans	240		271
% of Total Loans Using FICO Credit Metric	6.00%		6.00%
FICO score of less Than 620 [Member] | Other Consumer [Member]
Total Loans	554		602
% of Total Loans Using FICO Credit Metric	5.00%		5.00%
No FICO score available or required [Member] | Credit Card [Member]
Total Loans	384		428
% of Total Loans Using FICO Credit Metric	9.00%		10.00%
No FICO score available or required [Member] | Other Consumer [Member]
Total Loans	351		741
% of Total Loans Using FICO Credit Metric	3.00%		6.00%
Total Loans Using FICO Credit Metric [Member] | Credit Card [Member]
Total Loans	4,135		4,303
% of Total Loans Using FICO Credit Metric	100.00%		100.00%
Total Loans Using FICO Credit Metric [Member] | Other Consumer [Member]
Total Loans	12,306		11,704
% of Total Loans Using FICO Credit Metric	100.00%		100.00%
Other Internal Credit Metrics [Member] | Other Consumer [Member]
Total Loans	$ 8,871		$ 9,747
Pennsylvania [Member] | Credit Card [Member]
Percentage Of Higher Risk Credit Card Loans	15.00%		14.00%
Ohio [Member] | Credit Card [Member]
Percentage Of Higher Risk Credit Card Loans	19.00%		18.00%
Illinois [Member] | Credit Card [Member]
Percentage Of Higher Risk Credit Card Loans	7.00%		8.00%
Michigan [Member] | Credit Card [Member]
Percentage Of Higher Risk Credit Card Loans	12.00%		12.00%
Indiana [Member] | Credit Card [Member]
Percentage Of Higher Risk Credit Card Loans	6.00%		6.00%
Florida [Member] | Credit Card [Member]
Percentage Of Higher Risk Credit Card Loans	5.00%		6.00%
Kentucky [Member] | Credit Card [Member]
Percentage Of Higher Risk Credit Card Loans	5.00%		4.00%
New Jersey [Member] | Credit Card [Member]
Percentage Of Higher Risk Credit Card Loans	5.00%		5.00%
North Carolina [Member] | Credit Card [Member]
Percentage Of Higher Risk Credit Card Loans			4.00%
All Other States [Member] | Credit Card [Member]
Percentage Of Higher Risk Credit Card Loans	4.00%		3.00%

[1] Amounts represent the assets or liabilities of consolidated variable interest entities (VIEs).

[2] Amounts represent items for which the Corporation has elected the fair value option.