v2.4.0.8
Summary of Significant Accounting Policies (Details) (USD $)
In Millions, unless otherwise specified
 6 Months Ended
Jun. 30, 2013
Jun. 30, 2012
Jun. 30, 2013
Government insured/guaranteed [Member]
Jun. 30, 2012
Government insured/guaranteed [Member]
Jul. 31, 2013
Private Forward Repurchase Transaction [Member]
Jun. 30, 2013
Private Forward Repurchase Transaction [Member]
Supplemental cash flow information - Noncash activities            
Transfers from (to) loans to (from) securities available for sale $ 414 $ 875        
Trading assets retained from securitizations of MHFS 29,074 51,557        
Capitalization of MSRs from sale of MHFS 2,081 2,657        
Transfers from MHFS to foreclosed assets 31 115        
Transfers from loans to MHFS 4,855 2,858        
Transfers from loans to LHFS 133 49        
Transfers from loans to foreclosed assets 3,072 4,639 2,200 3,200    
Changes in consolidations (deconsolidations) of variable interest entities:            
Loans (306) (515)        
Long-term debt (343) (523)        
Summary Of Significant Accounting Policies Textuals [Abstract]            
Forward Contract Indexed to Issuer's Equity, Contract Amount         $ 500 $ 500