v2.4.0.8
Fair Value, Transfers Between Fair Value Levels (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 6 Months Ended
Jun. 30, 2013
Jun. 30, 2012
Jun. 30, 2013
Jun. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Total $ 0 $ 0 $ 0 $ 0
Trading Securities [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Total 0 0 0 0
Available for sale Securities [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Total 0 0 0 0
Mortgages held for sale [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Total 0 0 0 0
Loans [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Total 0 0 0 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 0 0 0
Level 1 [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Transfer In 0 0 17 0
Transfer Out (246) 0 (246) 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 0 0 0 0
Transfer Out (246) 0 (246) 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 0 0 17 0
Transfer Out 0 0 0 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 0 0 0
Transfer Out 0 0 0 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 0 0 0
Transfer Out 0 0 0 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 0 0 0
Transfer Out 0 0 0 0
Level 2 [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Transfer In 605 4,008 11,603 4,209
Transfer Out (82) (98) (221) (234)
Level 2 [Member] | Trading Securities [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Transfer In 266 0 468 10
Transfer Out (1) 0 (26) (14)
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 165 3,943 10,841 4,036
Transfer Out 0 (14) (17) (57)
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 46 64 139 150
Transfer Out (81) (84) (178) (171)
Level 2 [Member] | Loans [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Transfer In 58 0 106 0
Transfer Out 0 0 0 0
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 70 1 49 13
Transfer Out 0 0 0 8
Level 3 [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Transfer In 82 98 204 234
Transfer Out (359) (4,008) (11,357) (4,209)
Level 3 [Member] | Trading Securities [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Transfer In 1 0 26 14
Transfer Out (20) 0 (222) (10)
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 0 14 0 57
Transfer Out (165) (3,943) (10,841) (4,036)
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 81 84 178 171
Transfer Out (46) (64) (139) (150)
Level 3 [Member] | Loans [Member]
        
Fair Value, Assets and Liabilities Measured on Recurring Basis Transfers Between Fair Value Levels [Line Items]        
Transfer In 0 0 0 0
Transfer Out (58) 0 (106) 0
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 0 0 0 (8)
Transfer Out $ (70) $ (1) $ (49) $ (13)