Quarterly report pursuant to Section 13 or 15(d)

Derivatives Derivatives - Valuation Adjustments (Details)

v2.4.0.6
Derivatives Derivatives - Valuation Adjustments (Details) (USD $)
 3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Dec. 31, 2012
Derivative [Line Items]      
Credit Valuation Gains Losses Net Of Hedges Recognized In Trading Account Profits For Counterparty Credit Risk $ (102,000,000) [1] $ 221,000,000 [1]  
Credit Valuation Gain (Loss) Recognized In Trading Account Profit (Loss) Related to Changes in the Entity Credit Quality 124,000,000 [2] (624,000,000) [2]  
Credit Valuation Gains (Losses) For Counterparty Credit Risk Related To Derivative Assets (76,000,000) [1] 245,000,000 [1]  
Derivative Credit Risk Valuation Adjustment, Derivative Assets 1,200,000,000   1,100,000,000
Derivative Credit Risk Valuation Adjustment, Derivative Liabilities 500,000,000   400,000,000
Credit Valuation Gains (Losses) Net of Hedges Recognized In Trading Account Profit (Loss) 129,000,000 [2] (696,000,000) [2]  
Change in Calculation Methodology [Member]
      
Derivative [Line Items]      
Net Debit Valuation Adjustment (Gain) Loss, Excluding Impact of Change in Calculation Methodology 77,000,000    
Net Credit Valuation Adjustment Gain (Loss), Excluding Impact of Change in Calculation Methodology 104,000,000    
Increase (Decrease) in Derivative Valuation Adjustment Related to Change in Calculation Methodology 206,000,000    
Credit Valuation Gain (Loss) Recognized In Trading Account Profit (Loss) Related to Changes in the Entity Credit Quality $ 206,000,000    
[1] At March 31, 2013 and December 31, 2012, the cumulative counterparty credit risk valuation adjustment reduced the derivative assets balance by $1.2 billion and $1.1 billion.
[2] At March 31, 2013 and December 31, 2012, Merrill Lynch's cumulative DVA reduced the derivative liabilities balance by $0.5 billion and $0.4 billion