v2.4.0.6
Mortgage Banking Activities Textuals (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2012
Mar. 31, 2011
Dec. 31, 2011
Dec. 31, 2010
Mortgage Banking Activities (Textual) [Abstract]        
Cumulative effect of fair value election for certain residential mortgage servicing rights $ 2      
Amortization (58) (64)    
Retained earnings [Member]
       
Mortgage Banking Activities (Textual) [Abstract]        
Cumulative effect of fair value election for certain residential mortgage servicing rights 2      
Liability for mortgage loans repurchase losses [Member]
       
Mortgage Banking Activities (Textual) [Abstract]        
Loss Contingency, Range of Possible Loss, Portion Not Accrued 2,300      
Commercial Mortgage Servicing [Member]
       
Mortgage Banking Activities (Textual) [Abstract]        
Fair Value of amortized MSRs 1,263 1,453    
Residential Mortgage Servicing [Member]
       
Mortgage Banking Activities (Textual) [Abstract]        
Amortization   (10)    
Fair Value of amortized MSRs   445    
Residential Mortgage Servicing [Member] | Election of fair value option [Member]
       
Mortgage Banking Activities (Textual) [Abstract]        
Residential MSRs transferred from amortized MSRs 315      
Amortized [Member]
       
Mortgage Banking Activities (Textual) [Abstract]        
Amortization (58) (64)    
Fair Value of amortized MSRs 1,263 1,898 1,756 1,812
Amortized [Member] | Residential Mortgage Servicing [Member]
       
Mortgage Banking Activities (Textual) [Abstract]        
Residential MSRs transferred to MSRs carried at Fair Value, Gross 350      
Residential MSRs transferred to MSRs carried at Fair Value, Net 313      
Balance of amortized MSRs   $ 390