Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Recurring Fair Value (Details)

v2.4.0.6
Fair Value Measurements - Recurring Fair Value (Details) (USD $)
 9 Months Ended
Sep. 30, 2012
Jun. 30, 2012
Dec. 31, 2011
Sep. 30, 2011
Jun. 30, 2011
Dec. 31, 2010
Assets            
Federal funds sold and securities borrowed or purchased under agreements to resell $ 104,494,000,000   $ 87,453,000,000      
Derivative assets 57,865,000,000   73,023,000,000      
Mortgage servicing rights 5,087,000,000 5,708,000,000 7,378,000,000 7,880,000,000 12,372,000,000 14,900,000,000
Loans held-for-sale 11,077,000,000   7,630,000,000      
Other assets 32,552,000,000   37,084,000,000      
Liabilities            
Federal funds purchased and securities loaned or sold under agreements to repurchase 53,635,000,000   34,235,000,000      
Long-term debt 49,912,000,000   46,239,000,000      
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount 1,700,000,000          
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount 350,000,000          
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount 785,000,000          
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount 40,000,000          
Fair Value, Measurements, Recurring [Member]
            
Assets            
Federal funds sold and securities borrowed or purchased under agreements to resell 104,494,000,000   87,453,000,000      
Total trading account assets 211,090,000,000   169,319,000,000      
Derivative assets 57,865,000,000 [1]   73,023,000,000 [1]      
Total available-for-sale debt securities 305,949,000,000   276,151,000,000      
Loans and leases 7,638,000,000   8,804,000,000      
Mortgage servicing rights 5,087,000,000   7,378,000,000      
Loans held-for-sale 11,077,000,000   7,630,000,000      
Other assets 32,552,000,000   37,084,000,000      
Total assets 735,752,000,000   666,842,000,000      
Liabilities            
Interest-bearing deposits in U.S. offices 2,449,000,000   3,297,000,000      
Federal funds purchased and securities loaned or sold under agreements to repurchase 53,635,000,000   34,235,000,000      
Total trading account liabilities 72,179,000,000   60,508,000,000      
Derivative liabilities 51,369,000,000 [1]   59,520,000,000 [1]      
Commercial paper and other short-term borrowings 4,278,000,000   6,558,000,000      
Accrued expenses and other liabilities 18,280,000,000   15,743,000,000      
Long-term debt 49,912,000,000   46,239,000,000      
Total liabilities 252,102,000,000   226,100,000,000      
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Federal funds sold and securities borrowed or purchased under agreements to resell    [2]      [3]      
Total trading account assets 111,727,000,000 [2]   82,455,000,000 [3]      
Derivative assets 2,857,000,000 [1],[2]   2,186,000,000 [1],[3]      
Total available-for-sale debt securities 25,157,000,000 [2]   41,073,000,000 [3]      
Loans and leases    [2]      [3]      
Mortgage servicing rights    [2]      [3]      
Loans held-for-sale    [2]      [3]      
Other assets 18,651,000,000 [2]   18,963,000,000 [3]      
Total assets 158,392,000,000 [2]   144,677,000,000 [3]      
Liabilities            
Interest-bearing deposits in U.S. offices    [2]      [3]      
Federal funds purchased and securities loaned or sold under agreements to repurchase    [2]      [3]      
Total trading account liabilities 59,395,000,000 [2]   49,968,000,000 [3]      
Derivative liabilities 2,625,000,000 [1],[2]   2,055,000,000 [1],[3]      
Commercial paper and other short-term borrowings    [2]      [3]      
Accrued expenses and other liabilities 16,999,000,000 [2]   13,832,000,000 [3]      
Long-term debt    [2]      [3]      
Total liabilities 79,019,000,000 [2]   65,855,000,000 [3]      
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Federal funds sold and securities borrowed or purchased under agreements to resell 104,494,000,000 [2]   87,453,000,000 [3]      
Total trading account assets 89,408,000,000 [2]   75,409,000,000 [3]      
Derivative assets 1,456,794,000,000 [1],[2]   1,865,310,000,000 [1],[3]      
Total available-for-sale debt securities 274,493,000,000 [2]   227,066,000,000 [3]      
Loans and leases 5,385,000,000 [2]   6,060,000,000 [3]      
Mortgage servicing rights    [2]   0 [3]      
Loans held-for-sale 7,764,000,000 [2]   4,243,000,000 [3]      
Other assets 10,923,000,000 [2]   13,886,000,000 [3]      
Total assets 1,949,261,000,000 [2]   2,279,427,000,000 [3]      
Liabilities            
Interest-bearing deposits in U.S. offices 2,449,000,000 [2]   3,297,000,000 [3]      
Federal funds purchased and securities loaned or sold under agreements to repurchase 53,635,000,000 [2]   34,235,000,000 [3]      
Total trading account liabilities 12,619,000,000 [2]   10,426,000,000 [3]      
Derivative liabilities 1,441,542,000,000 [1],[2]   1,850,804,000,000 [1],[3]      
Commercial paper and other short-term borrowings 4,046,000,000 [2]   6,558,000,000 [3]      
Accrued expenses and other liabilities 1,272,000,000 [2]   1,897,000,000 [3]      
Long-term debt 47,622,000,000 [2]   43,296,000,000 [3]      
Total liabilities 1,563,185,000,000 [2]   1,950,513,000,000 [3]      
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Federal funds sold and securities borrowed or purchased under agreements to resell              
Total trading account assets 9,955,000,000   11,455,000,000      
Derivative assets 9,983,000,000 [1]   14,366,000,000 [1] 16,000,000,000    
Total available-for-sale debt securities 6,299,000,000   8,012,000,000      
Loans and leases 2,253,000,000   2,744,000,000      
Mortgage servicing rights 5,087,000,000   7,378,000,000      
Loans held-for-sale 3,313,000,000 [4],[5]   3,387,000,000 [4],[5]      
Other assets 2,978,000,000   4,235,000,000      
Total assets 39,868,000,000   51,577,000,000      
Liabilities            
Interest-bearing deposits in U.S. offices              
Federal funds purchased and securities loaned or sold under agreements to repurchase              
Total trading account liabilities 165,000,000   114,000,000      
Derivative liabilities 7,023,000,000 [1]   8,500,000,000 [1] 9,800,000,000    
Commercial paper and other short-term borrowings 232,000,000           
Accrued expenses and other liabilities 9,000,000   14,000,000      
Long-term debt 2,290,000,000   2,943,000,000      
Total liabilities 9,719,000,000   11,571,000,000      
Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Federal funds sold and securities borrowed or purchased under agreements to resell    [6]      [6]      
Total trading account assets    [6]      [6]      
Derivative assets (1,411,769,000,000) [1],[6]   (1,808,839,000,000) [1],[6]      
Total available-for-sale debt securities    [6]      [6]      
Loans and leases    [6]      [6]      
Mortgage servicing rights    [6]      [6]      
Loans held-for-sale    [6]      [6]      
Other assets    [6]      [6]      
Total assets (1,411,769,000,000) [6]   (1,808,839,000,000) [6]      
Liabilities            
Interest-bearing deposits in U.S. offices    [6]      [6]      
Federal funds purchased and securities loaned or sold under agreements to repurchase    [6]      [6]      
Total trading account liabilities    [6]      [6]      
Derivative liabilities (1,399,821,000,000) [1],[6]   (1,801,839,000,000) [1],[6]      
Commercial paper and other short-term borrowings    [6]      [6]      
Accrued expenses and other liabilities    [6]      [6]      
Long-term debt    [6]      [6]      
Total liabilities (1,399,821,000,000) [6]   (1,801,839,000,000) [6]      
US Government Corporations and Agencies Securities [Member] | Fair Value, Measurements, Recurring [Member]
            
Liabilities            
Total trading account liabilities 18,651,000,000   20,710,000,000      
US Government Corporations and Agencies Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Liabilities            
Total trading account liabilities 18,055,000,000 [2]   19,120,000,000 [3]      
US Government Corporations and Agencies Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Liabilities            
Total trading account liabilities 596,000,000 [2]   1,590,000,000 [3]      
US Government Corporations and Agencies Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Liabilities            
Total trading account liabilities              
US Government Corporations and Agencies Securities [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Liabilities            
Total trading account liabilities    [6]      [6]      
Equity securities [Member] | Fair Value, Measurements, Recurring [Member]
            
Liabilities            
Total trading account liabilities 22,360,000,000   14,594,000,000      
Equity securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Liabilities            
Total trading account liabilities 19,901,000,000 [2]   13,259,000,000 [3]      
Equity securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Liabilities            
Total trading account liabilities 2,459,000,000 [2]   1,335,000,000 [3]      
Equity securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Liabilities            
Total trading account liabilities              
Equity securities [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Liabilities            
Total trading account liabilities    [6]      [6]      
Foreign Government Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
            
Liabilities            
Total trading account liabilities 22,201,000,000   17,440,000,000      
Foreign Government Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Liabilities            
Total trading account liabilities 21,036,000,000 [2]   16,760,000,000 [3]      
Foreign Government Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Liabilities            
Total trading account liabilities 1,165,000,000 [2]   680,000,000 [3]      
Foreign Government Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Liabilities            
Total trading account liabilities              
Foreign Government Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Liabilities            
Total trading account liabilities    [6]      [6]      
Corporate securities, trading loans and other [Member] | Fair Value, Measurements, Recurring [Member]
            
Liabilities            
Total trading account liabilities 8,967,000,000   7,764,000,000      
Corporate securities, trading loans and other [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Liabilities            
Total trading account liabilities 403,000,000 [2]   829,000,000 [3]      
Corporate securities, trading loans and other [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Liabilities            
Total trading account liabilities 8,399,000,000 [2]   6,821,000,000 [3]      
Corporate securities, trading loans and other [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Liabilities            
Total trading account liabilities 165,000,000   114,000,000      
Corporate securities, trading loans and other [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Liabilities            
Total trading account liabilities    [6]      [6]      
U.S. government and agency securities [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total trading account assets 67,539,000,000   52,613,000,000      
U.S. government and agency securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total trading account assets 42,933,000,000 [2]   30,540,000,000 [3]      
U.S. government and agency securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total trading account assets 24,606,000,000 [2]   22,073,000,000 [3]      
U.S. government and agency securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total trading account assets              
U.S. government and agency securities [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total trading account assets    [6]      [6]      
Corporate securities and other [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total trading account assets 33,912,000,000   36,571,000,000      
Corporate securities and other [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total trading account assets 1,137,000,000 [2]   1,067,000,000 [3]      
Corporate securities and other [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total trading account assets 28,602,000,000 [2]   28,624,000,000 [3]      
Corporate securities and other [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total trading account assets 4,173,000,000   6,880,000,000      
Corporate securities and other [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total trading account assets    [6]      [6]      
Equity securities [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total trading account assets 38,825,000,000   23,674,000,000      
Equity securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total trading account assets 26,366,000,000 [2]   17,181,000,000 [3]      
Equity securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total trading account assets 11,886,000,000 [2]   5,949,000,000 [3]      
Equity securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total trading account assets 573,000,000   544,000,000      
Equity securities [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total trading account assets    [6]      [6]      
Non-U.S. sovereign debt [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total trading account assets 54,218,000,000   42,946,000,000      
Non-U.S. sovereign debt [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total trading account assets 41,291,000,000 [2]   33,667,000,000 [3]      
Non-U.S. sovereign debt [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total trading account assets 12,624,000,000 [2]   8,937,000,000 [3]      
Non-U.S. sovereign debt [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total trading account assets 303,000,000   342,000,000      
Non-U.S. sovereign debt [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total trading account assets    [6]      [6]      
Mortgage trading loans and ABS [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total trading account assets 16,596,000,000   13,515,000,000      
Mortgage trading loans and ABS [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total trading account assets    [2]      [3]      
Mortgage trading loans and ABS [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total trading account assets 11,690,000,000 [2]   9,826,000,000 [3]      
Mortgage trading loans and ABS [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total trading account assets 4,906,000,000   3,689,000,000      
Mortgage trading loans and ABS [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total trading account assets    [6]      [6]      
U.S. Treasury securities and agency securities [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total available-for-sale debt securities 24,795,000,000   42,864,000,000      
U.S. Treasury securities and agency securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total available-for-sale debt securities 21,815,000,000 [2]   39,389,000,000 [3]      
U.S. Treasury securities and agency securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total available-for-sale debt securities 2,980,000,000 [2]   3,475,000,000 [3]      
U.S. Treasury securities and agency securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total available-for-sale debt securities              
U.S. Treasury securities and agency securities [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total available-for-sale debt securities    [6]      [6]      
Agency [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total available-for-sale debt securities 204,043,000,000   142,563,000,000      
Agency [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total available-for-sale debt securities    [2]      [3]      
Agency [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total available-for-sale debt securities 204,043,000,000 [2]   142,526,000,000 [3]      
Agency [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total available-for-sale debt securities 0   37,000,000      
Agency [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total available-for-sale debt securities    [6]      [6]      
Agency-collateralized mortgage obligations [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total available-for-sale debt securities 40,147,000,000   44,999,000,000      
Agency-collateralized mortgage obligations [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total available-for-sale debt securities    [2]      [3]      
Agency-collateralized mortgage obligations [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total available-for-sale debt securities 40,147,000,000 [2]   44,999,000,000 [3]      
Agency-collateralized mortgage obligations [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total available-for-sale debt securities              
Agency-collateralized mortgage obligations [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total available-for-sale debt securities    [6]          
Non-agency residential [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total available-for-sale debt securities 10,002,000,000   14,767,000,000      
Non-agency residential [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total available-for-sale debt securities    [2]      [3]      
Non-agency residential [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total available-for-sale debt securities 10,001,000,000 [2]   13,907,000,000 [3]      
Non-agency residential [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total available-for-sale debt securities 1,000,000   860,000,000      
Non-agency residential [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total available-for-sale debt securities    [6]      [6]      
Non-agency commercial [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total available-for-sale debt securities 4,127,000,000   5,522,000,000      
Non-agency commercial [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total available-for-sale debt securities    [2]      [3]      
Non-agency commercial [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total available-for-sale debt securities 4,104,000,000 [2]   5,482,000,000 [3]      
Non-agency commercial [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total available-for-sale debt securities 23,000,000   40,000,000      
Non-agency commercial [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total available-for-sale debt securities    [6]      [6]      
Non-U.S. Securities [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total available-for-sale debt securities 5,748,000,000   4,920,000,000      
Non-U.S. Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total available-for-sale debt securities 3,322,000,000 [2]   1,664,000,000 [3]      
Non-U.S. Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total available-for-sale debt securities 2,426,000,000 [2]   3,256,000,000 [3]      
Non-U.S. Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total available-for-sale debt securities              
Non-U.S. Securities [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total available-for-sale debt securities    [6]      [6]      
Corporate/Agency bonds [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total available-for-sale debt securities 2,083,000,000   3,035,000,000      
Corporate/Agency bonds [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total available-for-sale debt securities    [2]      [3]      
Corporate/Agency bonds [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total available-for-sale debt securities 1,990,000,000 [2]   2,873,000,000 [3]      
Corporate/Agency bonds [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total available-for-sale debt securities 93,000,000   162,000,000      
Corporate/Agency bonds [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total available-for-sale debt securities    [6]      [6]      
Other taxable securities [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total available-for-sale debt securities 12,197,000,000   12,878,000,000      
Other taxable securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total available-for-sale debt securities 20,000,000 [2]   20,000,000 [3]      
Other taxable securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total available-for-sale debt securities 7,056,000,000 [2]   8,593,000,000 [3]      
Other taxable securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total available-for-sale debt securities 5,121,000,000   4,265,000,000      
Other taxable securities [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total available-for-sale debt securities    [6]      [6]      
Tax-exempt securities [Member] | Fair Value, Measurements, Recurring [Member]
            
Assets            
Total available-for-sale debt securities 2,807,000,000   4,603,000,000      
Tax-exempt securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
            
Assets            
Total available-for-sale debt securities    [2]      [3]      
Tax-exempt securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
            
Assets            
Total available-for-sale debt securities 1,746,000,000 [2]   1,955,000,000 [3]      
Tax-exempt securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
            
Assets            
Total available-for-sale debt securities 1,061,000,000   2,648,000,000      
Tax-exempt securities [Member] | Fair Value, Measurements, Recurring [Member] | Netting Adjustments [Member]
            
Assets            
Total available-for-sale debt securities    [6]      [6]      
Private Equity Investment [Member]
            
Liabilities            
Fair Value, Level 1 to level 2 Transfers, Amount 640,000,000          
Fair Value, Level 2 to level 1 Transfers, Amount $ 535,000,000          
[1] For further disaggregation of derivative assets and liabilities, see Note 3 – Derivatives.
[2] During the nine months ended September 30, 2012, $1.7 billion and $350 million of assets and liabilities were transferred from Level 1 to Level 2, and $785 million and $40 million of assets and liabilities were transferred from Level 2 to Level 1. Of the asset transfers from Level 1 to Level 2, $640 million were due to a restriction that became effective for a private equity investment during the first quarter of 2012, while $535 million of the transfers from Level 2 to Level 1 were due to the lapse of this restriction during the second quarter of 2012. The remaining transfers were the result of additional information associated with certain equities, derivative contracts and private equity investments.
[3] Gross transfers between Level 1 and Level 2 during 2011 were not significant.
[4] Amounts represent items that are accounted for under the fair value option.
[5] Assets (liabilities). For assets, increase / (decrease) to Level 3 and for liabilities, (increase) / decrease to Level 3.
[6] Amounts represent the impact of legally enforceable master netting agreements and also cash collateral held or placed with the same counterparties.