v2.4.0.6
Fair Value, Estimates for Financial Instruments Not Carried at Fair Value (Details) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Dec. 31, 2008
Dec. 31, 2007
Assets:          
Mortgages held for sale $ 48,357 $ 51,763      
Loans held for sale 1,338 1,290      
Loans 769,631 757,267 782,770 864,830 382,195
Nonmarketable equity investments (cost method) 8,061 8,494      
Liabilities:          
Deposits 920,070 847,942      
Long-term debt 125,354 156,983      
Carrying amount [Member]
         
Assets:          
Mortgages held for sale 3,566 4,232      
Loans held for sale 162 417      
Loans 731,308 721,016      
Nonmarketable equity investments (cost method) 8,061 8,494      
Liabilities:          
Deposits 920,070 847,942      
Long-term debt 125,238 156,651      
Estimated fair value [Member]
         
Assets:          
Mortgages held for sale 3,566 4,234      
Loans held for sale 176 441      
Loans 723,867 710,147      
Nonmarketable equity investments (cost method) 8,490 8,814      
Liabilities:          
Deposits 921,803 849,642      
Long-term debt $ 126,484 $ 159,996