v2.4.0.8
Mortgage Banking Activities Textuals (Details) (USD $)
12 Months Ended
Dec. 31, 2011
Dec. 31, 2011
Retained earnings [Member]
Jun. 30, 2013
Liability For Mortgage Loans Repurchase Losses [Member]
Jun. 30, 2013
Residential Mortgage Servicing [Member]
Jun. 30, 2013
Residential Mortgage Servicing [Member]
Election of fair value option [Member]
Jun. 30, 2013
Amortized [Member]
Mar. 31, 2013
Amortized [Member]
Dec. 31, 2012
Amortized [Member]
Jun. 30, 2012
Amortized [Member]
Mar. 31, 2012
Amortized [Member]
Dec. 31, 2011
Amortized [Member]
Jun. 30, 2013
Amortized [Member]
Residential Mortgage Servicing [Member]
Mortgage Banking Activities (Textual) [Abstract]                        
Residential MSRs transferred from amortized MSRs         $ 315,000,000              
Residential MSRs transferred to MSRs carried at Fair Value, Gross                       350,000,000
Residential MSRs transferred to MSRs carried at Fair Value, Net                       313,000,000
Cumulative effect of fair value election for certain residential mortgage servicing rights 2,000,000 2,000,000                    
Fair Value of amortized MSRs       316,000,000   1,533,000,000 1,404,000,000 1,400,000,000 1,450,000,000 1,263,000,000 1,756,000,000  
Loss Contingency, Range of Possible Loss, Portion Not Accrued     $ 2,200,000,000