v2.4.0.6
Loans and Allowance for Credit Losses, Allowance for Credit Losses by Category (Details) (USD $)
In Millions, unless otherwise specified
 12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Dec. 31, 2008
Financing Receivable, Allowance for Credit Losses [Roll Forward]          
Allowance for credit losses, beginning balance $ 19,668 $ 23,463 $ 25,031 $ 21,711 $ 5,518
Provision for credit losses 7,217 7,899 15,753 21,668 15,979
Interest income on certain impaired loans (315) (332) (266) 0 0
Loan charge-offs (10,973) (13,615) (20,100) (19,825) (8,777)
Loan recoveries 1,939 2,316 2,347 1,657 938
Net loan charge-offs (9,034) (11,299) (17,753) (18,168) (7,839)
Allowances related to business combinations/other (59) (63) 698 (180) 8,053
Allowance for credit losses, ending balance 17,477 19,668 23,463 25,031 21,711
Commercial Portfolio Segment [Member]
          
Financing Receivable, Allowance for Credit Losses [Roll Forward]          
Allowance for credit losses, beginning balance 6,358 8,169      
Provision for credit losses 666 365      
Interest income on certain impaired loans (95) (161)      
Loan charge-offs (2,014) (2,796) (5,433) (5,564) (2,170)
Loan recoveries 799 777 678 363 184
Net loan charge-offs (1,215) (2,019)      
Allowances related to business combinations/other 0 4      
Allowance for credit losses, ending balance 5,714 6,358 8,169    
Consumer Portfolio Segment [Member]
          
Financing Receivable, Allowance for Credit Losses [Roll Forward]          
Allowance for credit losses, beginning balance 13,310 15,294      
Provision for credit losses 6,551 7,534      
Interest income on certain impaired loans (220) (171)      
Loan charge-offs (8,959) (10,819) (14,667) (14,261) (6,607)
Loan recoveries 1,140 1,539 1,669 1,294 754
Net loan charge-offs (7,819) (9,280)      
Allowances related to business combinations/other (59) (67)      
Allowance for credit losses, ending balance $ 11,763 $ 13,310 $ 15,294