Annual report pursuant to Section 13 and 15(d)

Derivatives - Credit-related Contingent Features and Collateral (Details)

v2.4.0.6
Derivatives - Credit-related Contingent Features and Collateral (Details) (USD $)
Dec. 31, 2012
Dec. 31, 2011
Derivative [Line Items]    
Collateral Held, Cash and Securities $ 85,600,000,000 $ 87,700,000,000
Collateral Already Posted, Aggregate Fair Value 74,100,000,000 86,500,000,000
Colateral Not Yet Posted Aggregate Fair Value 2,200,000,000  
Unilateral Derivative Termination Contract [Member]
   
Derivative [Line Items]    
Collateral Already Posted, Aggregate Fair Value 1,600,000,000  
Derivative Liability, Fair Value, Amount Offset Against Collateral 1,652,000,000  
Unilateral Derivative Termination Contract For Rating Downgrade of Long-Term Senior Debt [Member]
   
Derivative [Line Items]    
Collateral Already Posted, Aggregate Fair Value 3,000,000,000  
Derivative Liability, Fair Value, Amount Offset Against Collateral 3,800,000,000  
Bank of America, N.A. [Member]
   
Derivative [Line Items]    
Colateral Not Yet Posted Aggregate Fair Value 721,000,000  
Merrill Lynch [Member]
   
Derivative [Line Items]    
Colateral Not Yet Posted Aggregate Fair Value 1,500,000,000  
Rating Agency Downgrade By One Notch [Member]
   
Derivative [Line Items]    
Additional Collateral, Aggregate Fair Value 3,300,000,000  
Rating Agency Downgrade By One Notch [Member] | Bank of America, N.A. [Member]
   
Derivative [Line Items]    
Additional Collateral, Aggregate Fair Value 2,900,000,000  
Rating Agency Downgrade By One Notch [Member] | Merrill Lynch [Member]
   
Derivative [Line Items]    
Additional Collateral, Aggregate Fair Value 418,000,000  
Rating Agency Downgrade by Two Notches [Member]
   
Derivative [Line Items]    
Additional Collateral, Aggregate Fair Value 4,400,000,000  
Rating Agency Downgrade by Two Notches [Member] | Unilateral Derivative Termination Contract For Rating Downgrade of Long-Term Senior Debt [Member]
   
Derivative [Line Items]    
Collateral Already Posted, Aggregate Fair Value 1,100,000,000  
Derivative Liability, Incremental Increase, Fair Value, Amount Offset Against Collateral 1,700,000,000  
Rating Agency Downgrade by Two Notches [Member] | Bank of America, N.A. [Member]
   
Derivative [Line Items]    
Additional Collateral, Aggregate Fair Value 455,000,000  
Rating Agency Downgrade by Two Notches [Member] | Merrill Lynch [Member]
   
Derivative [Line Items]    
Additional Collateral, Aggregate Fair Value $ 3,966,000,000