v2.4.0.6
Loans and Allowance for Credit Losses, Loans by Credit Impairment Methodology (Details) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Dec. 31, 2008
Dec. 31, 2007
Loans and Allowance for Credit Losses, by Credit Impairment Method [Abstract]            
Allowance for Credit Losses, Collectively evaluated $ 11,475 $ 12,759        
Allowance for Credit Losses, Individually evaluated 5,885 6,678        
Allowance for Credit Losses, Purchased Credit-Impaired 117 231 298 333    
Total allowance for credit losses 17,477 19,668 23,463 25,031 21,711 5,518
Financing Receivable, Collectively evaluated 738,594 704,902        
Financing Receivable, Individually evaluated 30,012 28,010        
Purchased Credit Impaired Loans 30,968 36,719 41,430 51,705 58,797  
Loans 799,574 769,631 757,267 782,770 864,830  
Commercial Portfolio Segment [Member]
            
Loans and Allowance for Credit Losses, by Credit Impairment Method [Abstract]            
Allowance for Credit Losses, Collectively evaluated 3,951 4,060        
Allowance for Credit Losses, Individually evaluated 1,675 2,133        
Allowance for Credit Losses, Purchased Credit-Impaired 88 165        
Total allowance for credit losses 5,714 6,358 8,169      
Financing Receivable, Collectively evaluated 349,035 328,117        
Financing Receivable, Individually evaluated 8,186 10,566        
Purchased Credit Impaired Loans 3,977 6,767 7,935 12,988 18,704  
Loans 361,198 345,450 322,058 336,465 389,964  
Consumer Portfolio Segment [Member]
            
Loans and Allowance for Credit Losses, by Credit Impairment Method [Abstract]            
Allowance for Credit Losses, Collectively evaluated 7,524 8,699        
Allowance for Credit Losses, Individually evaluated 4,210 4,545        
Allowance for Credit Losses, Purchased Credit-Impaired 29 66        
Total allowance for credit losses 11,763 13,310 15,294      
Financing Receivable, Collectively evaluated 389,559 376,785        
Financing Receivable, Individually evaluated 21,826 17,444        
Purchased Credit Impaired Loans 26,991 29,952 33,495 38,717 40,093  
Loans $ 438,376 $ 424,181 $ 435,209 $ 446,305 $ 474,866