v2.4.0.6
Loans and Allowance for Credit Losses, Loans by FICO Score, Consumer (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2013
Dec. 31, 2012
Dec. 31, 2008
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Purchased Credit Impaired Loans (carrying value) $ 29,729 $ 30,968 $ 58,797
Loans 799,966 799,574  
Total Consumer [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Purchased Credit Impaired Loans (carrying value) 26,227 26,991 40,093
Loans 438,252 438,376  
Real estate 1-4 family first mortgage [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Purchased Credit Impaired Loans (carrying value) 26,086 26,839 39,214
Loans 252,307 249,900  
Real estate 1-4 family junior lien mortgage [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Purchased Credit Impaired Loans (carrying value) 141 152 728
Loans 72,543 75,465  
Credit Card [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Purchased Credit Impaired Loans (carrying value) 0 0  
Loans 24,120 24,640  
Automobile [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Purchased Credit Impaired Loans (carrying value) 0 0 151
Loans 47,259 45,998  
Other revolving credit and installment [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Purchased Credit Impaired Loans (carrying value) 0 0  
Loans 42,023 42,373  
Loans Excluding Purchased Credit-Impaired Loans [Member] | Total Consumer [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Less than 600 35,356 35,189  
600-639 22,288 22,232  
640-679 36,423 36,263  
680-719 52,455 52,716  
720-759 62,684 63,337  
760-799 103,112 102,300  
Greater than 800 44,456 43,148  
No FICO available 7,908 8,632  
FICO not required 5,072 5,403  
Government insured/guaranteed loans 42,271 42,165  
Loans, excluding Purchased Credit Impaired Loans 412,025 411,385  
Loans Excluding Purchased Credit-Impaired Loans [Member] | Real estate 1-4 family first mortgage [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Less than 600 17,358 17,662  
600-639 10,055 10,208  
640-679 15,852 15,764  
680-719 24,669 24,725  
720-759 31,648 31,502  
760-799 65,842 63,946  
Greater than 800 27,530 26,044  
No FICO available 2,900 3,491  
FICO not required 0 0  
Government insured/guaranteed loans 30,367 29,719  
Loans, excluding Purchased Credit Impaired Loans 226,221 223,061  
Loans Excluding Purchased Credit-Impaired Loans [Member] | Real estate 1-4 family junior lien mortgage [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Less than 600 5,935 6,122  
600-639 3,576 3,660  
640-679 6,419 6,574  
680-719 11,012 11,361  
720-759 15,218 15,992  
760-799 20,773 21,874  
Greater than 800 8,323 8,526  
No FICO available 1,146 1,204  
FICO not required 0 0  
Government insured/guaranteed loans 0 0  
Loans, excluding Purchased Credit Impaired Loans 72,402 75,313  
Loans Excluding Purchased Credit-Impaired Loans [Member] | Credit Card [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Less than 600 2,400 2,314  
600-639 1,965 1,961  
640-679 3,693 3,772  
680-719 4,846 4,990  
720-759 4,898 5,114  
760-799 3,843 4,109  
Greater than 800 1,998 2,223  
No FICO available 477 157  
FICO not required 0 0  
Government insured/guaranteed loans 0 0  
Loans, excluding Purchased Credit Impaired Loans 24,120 24,640  
Loans Excluding Purchased Credit-Impaired Loans [Member] | Automobile [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Less than 600 8,506 7,928  
600-639 5,716 5,451  
640-679 8,410 8,142  
680-719 8,141 7,949  
720-759 5,934 5,787  
760-799 5,568 5,400  
Greater than 800 4,648 4,443  
No FICO available 336 898  
FICO not required 0 0  
Government insured/guaranteed loans 0 0  
Loans, excluding Purchased Credit Impaired Loans 47,259 45,998  
Loans Excluding Purchased Credit-Impaired Loans [Member] | Other revolving credit and installment [Member]
      
Loans by FICO, Excluding Purchased Credit Impaired Loans [Abstract]      
Less than 600 1,157 1,163  
600-639 976 952  
640-679 2,049 2,011  
680-719 3,787 3,691  
720-759 4,986 4,942  
760-799 7,086 6,971  
Greater than 800 1,957 1,912  
No FICO available 3,049 2,882  
FICO not required 5,072 5,403  
Government insured/guaranteed loans 11,904 12,446  
Loans, excluding Purchased Credit Impaired Loans $ 42,023 $ 42,373