Loans and Allowance for Loan Losses (Details 8) (USD $) In Millions, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2014	Dec. 31, 2013
Consumer
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	$ 30,748	$ 28,821
Percentage of total	100.00%	100.00%
Consumer | FICO Score 720 and Above
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	23,674	21,991
Percentage of total	77.00%	76.00%
Consumer | FICO Score Below 720
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	6,467	6,275
Percentage of total	21.00%	22.00%
Consumer | No FICO Available
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	607	555
Percentage of total	2.00%	2.00%
Consumer portfolio
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	30,526	28,577
Consumer portfolio | FICO Score 720 and Above
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	23,587	21,897
Consumer portfolio | FICO Score Below 720
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	6,344	6,140
Consumer portfolio | No FICO Available
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	595	540
Consumer portfolio | Residential mortgage
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	27,408	25,374
Consumer portfolio | Residential mortgage | FICO Score 720 and Above
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	21,339	19,614
Consumer portfolio | Residential mortgage | FICO Score Below 720
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	5,554	5,301
Consumer portfolio | Residential mortgage | No FICO Available
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	515	459
Consumer portfolio | Home equity and other consumer loans
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	3,118	3,203
Consumer portfolio | Home equity and other consumer loans | FICO Score 720 and Above
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	2,248	2,283
Consumer portfolio | Home equity and other consumer loans | FICO Score Below 720
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	790	839
Consumer portfolio | Home equity and other consumer loans | No FICO Available
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	80	81
Purchased credit-impaired loans | Consumer
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	222	244
Purchased credit-impaired loans | Consumer | FICO Score 720 and Above
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	87	94
Purchased credit-impaired loans | Consumer | FICO Score Below 720
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	123	135
Purchased credit-impaired loans | Consumer | No FICO Available
Credit quality of consumer loans
Loan balances, excluding loans serviced by third parties and loans covered by FDIC loss share agreements	$ 12	$ 15