v2.4.0.6
Fair Value, Assets Recorded at Fair Value on a Nonrecurring Basis Level 3 Valuation Techniques and Significant Unobservable Inputs (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2012
Minimum [Member]
Mortgages held for sale [Member]
Discounted cash flow [Member]
Dec. 31, 2012
Minimum [Member]
Residential Portfolio Segment [Member]
Mortgages held for sale [Member]
Discounted cash flow [Member]
Dec. 31, 2012
Maximum [Member]
Mortgages held for sale [Member]
Discounted cash flow [Member]
Dec. 31, 2012
Maximum [Member]
Residential Portfolio Segment [Member]
Mortgages held for sale [Member]
Discounted cash flow [Member]
Dec. 31, 2012
Weighted Average [Member]
Mortgages held for sale [Member]
Discounted cash flow [Member]
Dec. 31, 2012
Weighted Average [Member]
Residential Portfolio Segment [Member]
Mortgages held for sale [Member]
Discounted cash flow [Member]
Dec. 31, 2012
Nonrecurring [Member]
Dec. 31, 2011
Nonrecurring [Member]
Dec. 31, 2012
Level 3 [Member]
Nonrecurring [Member]
Dec. 31, 2011
Level 3 [Member]
Nonrecurring [Member]
Dec. 31, 2012
Level 3 [Member]
Nonrecurring [Member]
Residential Portfolio Segment [Member]
Discounted cash flow [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]                          
Mortgages held for sale $ 42,305 $ 44,791             $ 2,554 $ 2,185 $ 1,045 $ 1,166 $ 1,045
Total insignificant level 3 assets                     148    
Total                     $ 1,193    
Fair Value Inputs [Abstract]                          
Discount rate     3.40% 4.10% 7.50% 11.90% 5.40% 10.90%          
Loss severity     1.30% 2.00% 35.30% 45.00% 26.40% 6.00%          
Default rate     0.60% 2.90% 14.80% 21.20% 5.50% 7.90%          
Prepayment rate     1.00% 1.00% 11.00% 100.00% 6.20% 66.70%