v2.4.0.6
Fair Value, Transfers Between Fair Value Levels (Details) (USD $)
In Millions, unless otherwise specified
 12 Months Ended
Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Total $ 0
Trading Securities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Total 0
Available for sale Securities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Total 0
Mortgages held for sale [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Total 0
Loans [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Total 0
Net derivative assets and liabilities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Total 0
Short sale liabilities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Total 0
Level 1 [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 31
Transfer Out 0
Level 1 [Member] | Trading Securities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 23
Transfer Out 0
Level 1 [Member] | Available for sale Securities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 8
Transfer Out 0
Level 1 [Member] | Mortgages held for sale [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 0
Transfer Out 0
Level 1 [Member] | Loans [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 0
Transfer Out 0
Level 1 [Member] | Net derivative assets and liabilities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 0
Transfer Out 0
Level 1 [Member] | Short sale liabilities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 0
Transfer Out 0
Level 2 [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 10,238
Transfer Out (6,436)
Level 2 [Member] | Trading Securities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 16
Transfer Out (37)
Level 2 [Member] | Available for sale Securities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 9,832
Transfer Out (68)
Level 2 [Member] | Mortgages held for sale [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 298
Transfer Out (488)
Level 2 [Member] | Loans [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 41
Transfer Out (5,851)
Level 2 [Member] | Net derivative assets and liabilities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 51
Transfer Out 8
Level 2 [Member] | Short sale liabilities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 0
Transfer Out 0
Level 3 [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 6,405
Transfer Out (10,238)
Level 3 [Member] | Trading Securities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 14
Transfer Out (16)
Level 3 [Member] | Available for sale Securities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 60
Transfer Out (9,832)
Level 3 [Member] | Mortgages held for sale [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 488
Transfer Out (298)
Level 3 [Member] | Loans [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 5,851
Transfer Out (41)
Level 3 [Member] | Net derivative assets and liabilities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In (8)
Transfer Out (51)
Level 3 [Member] | Short sale liabilities [Member]
  
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]  
Transfer In 0
Transfer Out $ 0