v2.4.0.6
Loans and Allowance for Credit Losses, Loans by Credit Impairment Methodology (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2012
Dec. 31, 2011
Mar. 31, 2011
Dec. 31, 2010
Loans and Allowance for Credit Losses, by Credit Impairment Method [Abstract]        
Allowance for Credit Losses, Collectively evaluated $ 12,354 $ 12,759    
Allowance for Credit Losses, Individually evaluated 6,530 6,678    
Allowance for Credit Losses, Purchased Credit-Impaired 245 231    
Total allowance for credit losses 19,129 19,668 22,383 23,463
Financing Receivable, Collectively evaluated 703,300 704,902    
Financing Receivable, Individually evaluated 27,687 28,010    
Purchased Credit Impaired Loans 35,534 36,719    
Loans 766,521 769,631    
Total Commercial [Member]
        
Loans and Allowance for Credit Losses, by Credit Impairment Method [Abstract]        
Allowance for Credit Losses, Collectively evaluated 3,939 4,060    
Allowance for Credit Losses, Individually evaluated 2,014 2,133    
Allowance for Credit Losses, Purchased Credit-Impaired 177 165    
Total allowance for credit losses 6,130 6,358 7,973 8,169
Financing Receivable, Collectively evaluated 329,382 328,117    
Financing Receivable, Individually evaluated 10,113 10,566    
Purchased Credit Impaired Loans 6,254 6,767    
Loans 345,749 345,450    
Total Consumer [Member]
        
Loans and Allowance for Credit Losses, by Credit Impairment Method [Abstract]        
Allowance for Credit Losses, Collectively evaluated 8,415 8,699    
Allowance for Credit Losses, Individually evaluated 4,516 4,545    
Allowance for Credit Losses, Purchased Credit-Impaired 68 66    
Total allowance for credit losses 12,999 13,310 14,410 15,294
Financing Receivable, Collectively evaluated 373,918 376,785    
Financing Receivable, Individually evaluated 17,574 17,444    
Purchased Credit Impaired Loans 29,280 29,952    
Loans $ 420,772 $ 424,181