v2.4.0.6
Loans and Allowance for Credit Losses, Significant Activity (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Loans and Allowance for Credit Losses, Significant Activity [Abstract]    
Purchases $ 12,447 $ 7,362
Sales (6,680) (5,723)
Transfers to mortgages/loans held for sale (105) (239)
Commercial Portfolio Segment [Member]
   
Loans and Allowance for Credit Losses, Significant Activity [Abstract]    
Purchases 12,280 7,078
Sales (5,840) (4,705)
Transfers to mortgages/loans held for sale (84) (164)
Consumer Portfolio Segment [Member]
   
Loans and Allowance for Credit Losses, Significant Activity [Abstract]    
Purchases 167 284
Sales (840) (1,018)
Transfers to mortgages/loans held for sale $ (21) $ (75)