v2.4.0.6
Derivatives, Net Gains (Losses) in Income related to Fair Value Hedges (Details) (USD $)
In Millions, unless otherwise specified
 12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Net Gains Losses Recognized In Income Statement Related To Derivatives In Fair Value Hedging Relationships [Abstract]    
Gains (losses) recorded in net interest income $ 1,573 $ 1,735
Gains (losses) recorded in noninterest income Recognized on derivatives 2,157 372
Gains (losses) recorded in noninterest income Recognized on hedged item (1,998) (263)
Gains (losses) recorded in noninterest income Recognized on fair value hedges (ineffective portion) 159 109
Available for sale Securities [Member] | Interest Rate Contract [Member]
    
Net Gains Losses Recognized In Income Statement Related To Derivatives In Fair Value Hedging Relationships [Abstract]    
Gains (losses) recorded in net interest income (451) (390)
Gains (losses) recorded in noninterest income Recognized on derivatives (1,298) (432)
Gains (losses) recorded in noninterest income Recognized on hedged item 1,232 469
Gains (losses) recorded in noninterest income Recognized on fair value hedges (ineffective portion) (66) 37
Available for sale Securities [Member] | Foreign Exchange Contract [Member]
    
Net Gains Losses Recognized In Income Statement Related To Derivatives In Fair Value Hedging Relationships [Abstract]    
Gains (losses) recorded in net interest income (11) (4)
Gains (losses) recorded in noninterest income Recognized on derivatives 168 269
Gains (losses) recorded in noninterest income Recognized on hedged item (186) (270)
Gains (losses) recorded in noninterest income Recognized on fair value hedges (ineffective portion) (18) (1)
Long-term debt [Member] | Interest Rate Contract [Member]
    
Net Gains Losses Recognized In Income Statement Related To Derivatives In Fair Value Hedging Relationships [Abstract]    
Gains (losses) recorded in net interest income 1,659 1,755
Gains (losses) recorded in noninterest income Recognized on derivatives 2,796 1,565
Gains (losses) recorded in noninterest income Recognized on hedged item (2,616) (1,469)
Gains (losses) recorded in noninterest income Recognized on fair value hedges (ineffective portion) 180 96
Long-term debt [Member] | Foreign Exchange Contract [Member]
    
Net Gains Losses Recognized In Income Statement Related To Derivatives In Fair Value Hedging Relationships [Abstract]    
Gains (losses) recorded in net interest income 376 374
Gains (losses) recorded in noninterest income Recognized on derivatives 512 (1,030)
Gains (losses) recorded in noninterest income Recognized on hedged item (445) 1,007
Gains (losses) recorded in noninterest income Recognized on fair value hedges (ineffective portion) 67 (23)
Mortgages held for sale [Member] | Interest Rate Contract [Member]
    
Net Gains Losses Recognized In Income Statement Related To Derivatives In Fair Value Hedging Relationships [Abstract]    
Gains (losses) recorded in net interest income 0 0
Gains (losses) recorded in noninterest income Recognized on derivatives (21) 0
Gains (losses) recorded in noninterest income Recognized on hedged item 17 0
Gains (losses) recorded in noninterest income Recognized on fair value hedges (ineffective portion) $ (4) $ 0