Fair Value Measurement - Recurring Basis (Details) (USD $)	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Mortgage servicing rights	$ 7,949,000,000	$ 7,614,000,000	$ 8,039,000,000	$ 7,223,000,000
Other assets, at fair value	102,101,000,000	101,775,000,000
Deposits, at fair value	1,202,507,000,000	1,193,593,000,000
Federal funds purchased and securities loaned or sold under repurchase agreements, at fair value	248,245,000,000	240,103,000,000
Other Short-term Borrowings	27,200,000,000	26,636,000,000
Beneficial interest liability, at fair value	58,300,000,000	63,191,000,000
Fair value assets and liabilities measured on recurring basis - supplemental data
Reduction In Level Three Derivative Receivable And Derivative Payable Balances	6,800,000,000	8,400,000,000
Costs of the private equity investment portfolio	8,600,000,000	8,400,000,000
Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	430,991,000,000	450,028,000,000
Mortgage servicing rights	7,949,000,000	7,614,000,000
Total assets measured at fair value on a recurring basis	854,018,000,000	882,235,000,000
Trading liabilities	125,726,000,000	131,918,000,000
Total liabilities at fair value on a recurring basis	181,771,000,000	185,624,000,000
Fair value assets and liabilities measured on recurring basis - supplemental data
Investment valued at net asset value	3,900,000,000	4,900,000,000
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Line Items]
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0	0
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Securities borrowed	0	0
Trading assets	161,948,000,000	159,512,000,000
Available-for-sale securities	46,732,000,000	43,413,000,000
Loans, at fair value	0	0
Mortgage servicing rights	0	0
Total assets measured at fair value on a recurring basis	213,456,000,000	207,691,000,000
Deposits	0	0
Federal funds purchased and securities loaned or sold under repurchase agreements (included $9.5 and $4.1 at fair value)	0	0
Other Short-term Borrowings	0	0
Trading liabilities	50,296,000,000	48,563,000,000
Accounts payable and other liabilities	0	0
Beneficial interests issued by consolidated VIEs, at fair value	0	0
Long-term debt	0	0
Total liabilities at fair value on a recurring basis	50,296,000,000	48,563,000,000
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Line Items]
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	25,616,000,000	24,258,000,000
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Securities borrowed	5,411,000,000	10,177,000,000
Trading assets	1,679,916,000,000	1,839,013,000,000
Available-for-sale securities	317,038,000,000	298,816,000,000
Loans, at fair value	97,000,000	273,000,000
Mortgage servicing rights	0	0
Total assets measured at fair value on a recurring basis	2,028,639,000,000	2,172,790,000,000
Deposits	4,014,000,000	3,750,000,000
Federal funds purchased and securities loaned or sold under repurchase agreements (included $9.5 and $4.1 at fair value)	4,380,000,000	4,388,000,000
Other Short-term Borrowings	11,681,000,000	9,972,000,000
Trading liabilities	1,498,914,000,000	1,640,684,000,000
Accounts payable and other liabilities	0	0
Beneficial interests issued by consolidated VIEs, at fair value	312,000,000	245,000,000
Long-term debt	21,571,000,000	22,312,000,000
Total liabilities at fair value on a recurring basis	1,540,872,000,000	1,681,351,000,000
Fair value assets and liabilities measured on recurring basis - supplemental data
Investment valued at net asset value	1,000,000,000	1,100,000,000
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Line Items]
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0	0
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Securities borrowed	0	0
Trading assets	44,560,000,000	48,897,000,000
Available-for-sale securities	1,967,000,000	28,916,000,000
Loans, at fair value	2,064,000,000	2,282,000,000
Mortgage servicing rights	7,949,000,000	7,614,000,000
Total assets measured at fair value on a recurring basis	67,356,000,000	99,148,000,000
Deposits	2,015,000,000	1,983,000,000
Federal funds purchased and securities loaned or sold under repurchase agreements (included $9.5 and $4.1 at fair value)	0	0
Other Short-term Borrowings	2,137,000,000	1,619,000,000
Trading liabilities	20,334,000,000	21,570,000,000
Accounts payable and other liabilities	33,000,000	36,000,000
Beneficial interests issued by consolidated VIEs, at fair value	818,000,000	925,000,000
Long-term debt	9,084,000,000	8,476,000,000
Total liabilities at fair value on a recurring basis	34,421,000,000	34,609,000,000
Fair value assets and liabilities measured on recurring basis - supplemental data
Investment valued at net asset value	2,900,000,000	3,800,000,000
Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Line Items]
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0	0
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Securities borrowed	0	0
Trading assets	(1,455,433,000,000)	(1,597,394,000,000)
Available-for-sale securities	0	0
Loans, at fair value	0	0
Mortgage servicing rights	0	0
Total assets measured at fair value on a recurring basis	(1,455,433,000,000)	(1,597,394,000,000)
Deposits	0	0
Federal funds purchased and securities loaned or sold under repurchase agreements (included $9.5 and $4.1 at fair value)	0	0
Other Short-term Borrowings	0	0
Trading liabilities	(1,443,818,000,000)	(1,578,899,000,000)
Accounts payable and other liabilities	0	0
Beneficial interests issued by consolidated VIEs, at fair value	0	0
Long-term debt	0	0
Total liabilities at fair value on a recurring basis	(1,443,818,000,000)	(1,578,899,000,000)
Fair value | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Line Items]
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	25,616,000,000	24,258,000,000
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Securities borrowed	5,411,000,000	10,177,000,000
Available-for-sale securities	365,737,000,000	371,145,000,000
Loans, at fair value	2,161,000,000	2,555,000,000
Deposits	6,029,000,000	5,733,000,000
Federal funds purchased and securities loaned or sold under repurchase agreements (included $9.5 and $4.1 at fair value)	4,380,000,000	4,388,000,000
Other Short-term Borrowings	13,818,000,000	11,591,000,000
Accounts payable and other liabilities	33,000,000	36,000,000
Long-term debt	30,655,000,000	30,788,000,000
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total assets measured at fair value on a recurring basis	118,000,000,000	119,400,000,000
Total debt and equity instruments [Member] | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	360,382,000,000	375,045,000,000
Trading liabilities	63,737,000,000	61,262,000,000
Total debt and equity instruments [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	160,588,000,000	158,270,000,000
Trading liabilities	48,814,000,000	47,469,000,000
Total debt and equity instruments [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	177,091,000,000	191,136,000,000
Trading liabilities	14,672,000,000	13,588,000,000
Total debt and equity instruments [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	22,703,000,000	25,639,000,000
Trading liabilities	251,000,000	205,000,000
Total debt and equity instruments [Member] | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Trading liabilities	0	0
Total debt instruments [Member] | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	237,542,000,000	243,827,000,000
Total debt instruments [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	51,218,000,000	41,265,000,000
Total debt instruments [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	165,741,000,000	178,900,000,000
Total debt instruments [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	20,583,000,000	23,662,000,000
Total debt instruments [Member] | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Mortgage-backed securities | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	35,959,000,000	41,682,000,000
Available-for-sale securities	184,837,000,000	186,230,000,000
Mortgage-backed securities | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Mortgage-backed securities | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	33,356,000,000	39,314,000,000
Available-for-sale securities	184,187,000,000	185,525,000,000
Mortgage-backed securities | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	2,603,000,000	2,368,000,000
Available-for-sale securities	650,000,000	705,000,000
Mortgage-backed securities | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
US Government Corporations and Agencies Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	31,197,000,000	36,738,000,000
Available-for-sale securities	104,264,000,000	98,388,000,000
US Government Corporations and Agencies Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
US Government Corporations and Agencies Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	30,378,000,000	36,240,000,000
Available-for-sale securities	104,264,000,000	98,388,000,000
US Government Corporations and Agencies Securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	819,000,000	498,000,000
Available-for-sale securities	0	0
US Government Corporations and Agencies Securities [Member] | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Residential mortgage | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	2,207,000,000	2,172,000,000
Available-for-sale securities	67,736,000,000	74,639,000,000
Residential mortgage | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Residential mortgage | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,574,000,000	1,509,000,000
Available-for-sale securities	67,358,000,000	74,189,000,000
Residential mortgage | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	633,000,000	663,000,000
Available-for-sale securities	378,000,000	450,000,000
Residential mortgage | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Commercial - nonagency | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	2,555,000,000	2,772,000,000
Available-for-sale securities	12,837,000,000	13,203,000,000
Commercial - nonagency | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Commercial - nonagency | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,404,000,000	1,565,000,000
Available-for-sale securities	12,565,000,000	12,948,000,000
Commercial - nonagency | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,151,000,000	1,207,000,000
Available-for-sale securities	272,000,000	255,000,000
Commercial - nonagency | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
U.S. Treasury and government agencies | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	27,221,000,000	22,425,000,000
Available-for-sale securities	11,930,000,000	12,130,000,000
U.S. Treasury and government agencies | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	20,265,000,000	15,170,000,000
Available-for-sale securities	10,912,000,000	11,089,000,000
U.S. Treasury and government agencies | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	6,956,000,000	7,255,000,000
Available-for-sale securities	1,018,000,000	1,041,000,000
U.S. Treasury and government agencies | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
U.S. Treasury and government agencies | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Obligations of U.S. states and municipalities | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	19,641,000,000	18,162,000,000
Available-for-sale securities	20,978,000,000	21,711,000,000
Obligations of U.S. states and municipalities | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	33,000,000	35,000,000
Obligations of U.S. states and municipalities | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	18,209,000,000	16,726,000,000
Available-for-sale securities	20,758,000,000	21,489,000,000
Obligations of U.S. states and municipalities | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,432,000,000	1,436,000,000
Available-for-sale securities	187,000,000	187,000,000
Obligations of U.S. states and municipalities | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Certificates Of Deposit Bankers Acceptances Commercial Paper [Member] | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	2,714,000,000	4,759,000,000
Certificates Of Deposit Bankers Acceptances Commercial Paper [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Certificates Of Deposit Bankers Acceptances Commercial Paper [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	2,714,000,000	4,759,000,000
Certificates Of Deposit Bankers Acceptances Commercial Paper [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Certificates Of Deposit Bankers Acceptances Commercial Paper [Member] | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Certificates of Deposit | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	2,379,000,000	2,783,000,000
Certificates of Deposit | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	0	0
Certificates of Deposit | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	2,379,000,000	2,783,000,000
Certificates of Deposit | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	0	0
Certificates of Deposit | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	0	0
Non-U.S. government debt securities | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	74,485,000,000	70,190,000,000
Available-for-sale securities	70,367,000,000	66,044,000,000
Non-U.S. government debt securities | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	30,953,000,000	26,095,000,000
Available-for-sale securities	33,313,000,000	29,556,000,000
Non-U.S. government debt securities | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	43,447,000,000	44,028,000,000
Available-for-sale securities	37,054,000,000	36,488,000,000
Non-U.S. government debt securities | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	85,000,000	67,000,000
Available-for-sale securities	0	0
Non-U.S. government debt securities | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Corporate Debt Securities | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	33,222,000,000	37,190,000,000
Available-for-sale securities	33,239,000,000	38,609,000,000
Corporate Debt Securities | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Corporate Debt Securities | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	28,370,000,000	31,882,000,000
Available-for-sale securities	33,239,000,000	38,609,000,000
Corporate Debt Securities | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	4,852,000,000	5,308,000,000
Available-for-sale securities	0	0
Corporate Debt Securities | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Loans | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	38,505,000,000	41,541,000,000
Loans | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Loans | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	28,473,000,000	30,754,000,000
Loans | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	10,032,000,000	10,787,000,000
Loans | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Residential Mortgage [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	22,700,000,000	26,400,000,000
Reverse Mortgage [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	3,700,000,000	4,000,000,000
Residential Conforming Mortgage Intended for Sale to Government Agency [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	15,000,000,000	17,400,000,000
Wholesale Loan [Member] | Trading assets
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	2,200,000,000	2,200,000,000
Asset-backed securities | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	5,795,000,000	7,878,000,000
Asset-backed securities | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Asset-backed securities | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	4,216,000,000	4,182,000,000
Asset-backed securities | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,579,000,000	3,696,000,000
Asset-backed securities | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Collateralized loan obligations | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	27,359,000,000	27,896,000,000
Collateralized loan obligations | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	0	0
Collateralized loan obligations | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	26,359,000,000	0
Collateralized loan obligations | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	1,000,000,000	27,896,000,000
Collateralized loan obligations | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	0	0
Other, Debt Securities | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	12,174,000,000	12,971,000,000
Other, Debt Securities | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	0	0
Other, Debt Securities | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	12,044,000,000	12,843,000,000
Other, Debt Securities | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	130,000,000	128,000,000
Other, Debt Securities | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	0	0
Equity securities | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	103,679,000,000	110,699,000,000
Available-for-sale securities	2,474,000,000	2,771,000,000
Equity securities | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	100,543,000,000	106,898,000,000
Available-for-sale securities	2,474,000,000	2,733,000,000
Equity securities | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,964,000,000	2,687,000,000
Available-for-sale securities	0	38,000,000
Equity securities | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,172,000,000	1,114,000,000
Available-for-sale securities	0	0
Equity securities | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Available-for-sale securities	0	0
Other equity instruments [Member] | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	4,884,000,000	4,346,000,000
Other equity instruments [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Other equity instruments [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	3,936,000,000	3,483,000,000
Other equity instruments [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	948,000,000	863,000,000
Other equity instruments [Member] | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Physical commodities [Member] | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	14,277,000,000	16,173,000,000
Physical commodities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	8,827,000,000	10,107,000,000
Physical commodities [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	5,450,000,000	6,066,000,000
Physical commodities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Physical commodities [Member] | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Credit Derivative [Member] | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	70,609,000,000	74,983,000,000
Trading liabilities	61,989,000,000	70,656,000,000
Credit Derivative [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,360,000,000	1,242,000,000
Trading liabilities	1,482,000,000	1,094,000,000
Credit Derivative [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,502,825,000,000	1,647,877,000,000
Trading liabilities	1,484,242,000,000	1,627,096,000,000
Credit Derivative [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	21,857,000,000	23,258,000,000
Trading liabilities	20,083,000,000	21,365,000,000
Credit Derivative [Member] | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	(1,455,433,000,000)	(1,597,394,000,000)
Trading liabilities	(1,443,818,000,000)	(1,578,899,000,000)
Interest rate contract | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	34,280,000,000	39,205,000,000
Trading liabilities	18,611,000,000	24,906,000,000
Interest rate contract | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	714,000,000	476,000,000
Trading liabilities	804,000,000	490,000,000
Interest rate contract | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,166,908,000,000	1,322,155,000,000
Trading liabilities	1,130,516,000,000	1,283,829,000,000
Interest rate contract | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	6,167,000,000	6,617,000,000
Trading liabilities	3,376,000,000	3,295,000,000
Interest rate contract | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	(1,139,509,000,000)	(1,290,043,000,000)
Trading liabilities	(1,116,085,000,000)	(1,262,708,000,000)
Credit derivatives | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	3,664,000,000	1,735,000,000
Trading liabilities	3,134,000,000	2,504,000,000
Credit derivatives | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Trading liabilities	0	0
Credit derivatives | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	98,137,000,000	93,821,000,000
Trading liabilities	97,405,000,000	95,411,000,000
Credit derivatives | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	5,262,000,000	6,489,000,000
Trading liabilities	3,945,000,000	4,616,000,000
Credit derivatives | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	(99,735,000,000)	(98,575,000,000)
Trading liabilities	(98,216,000,000)	(97,523,000,000)
Foreign exchange | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	12,346,000,000	14,142,000,000
Trading liabilities	14,806,000,000	18,601,000,000
Foreign exchange | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	472,000,000	450,000,000
Trading liabilities	439,000,000	428,000,000
Foreign exchange | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	138,511,000,000	144,758,000,000
Trading liabilities	151,951,000,000	156,413,000,000
Foreign exchange | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	2,508,000,000	3,051,000,000
Trading liabilities	4,024,000,000	4,801,000,000
Foreign exchange | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	(129,145,000,000)	(134,117,000,000)
Trading liabilities	(141,608,000,000)	(143,041,000,000)
Equity | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	10,035,000,000	9,266,000,000
Trading liabilities	13,347,000,000	11,819,000,000
Equity | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	0	0
Trading liabilities	0	0
Equity | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	40,321,000,000	37,741,000,000
Trading liabilities	41,591,000,000	37,807,000,000
Equity | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	6,117,000,000	4,921,000,000
Trading liabilities	7,117,000,000	6,727,000,000
Equity | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	(36,403,000,000)	(33,396,000,000)
Trading liabilities	(35,361,000,000)	(32,715,000,000)
Commodity Contract | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	10,284,000,000	10,635,000,000
Trading liabilities	12,091,000,000	12,826,000,000
Commodity Contract | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	174,000,000	316,000,000
Trading liabilities	239,000,000	176,000,000
Commodity Contract | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	58,948,000,000	49,402,000,000
Trading liabilities	62,779,000,000	53,636,000,000
Commodity Contract | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,803,000,000	2,180,000,000
Trading liabilities	1,621,000,000	1,926,000,000
Commodity Contract | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	(50,641,000,000)	(41,263,000,000)
Trading liabilities	(52,548,000,000)	(42,912,000,000)
Total other assets | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	4,776,000,000	4,766,000,000
Total other assets | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	561,000,000	253,000,000
Total other assets | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	10,816,000,000	11,439,000,000
Total other assets | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	0	0
Total other assets | Fair value | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	16,153,000,000	16,458,000,000
Private Equity Funds [Member] | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	7,409,000,000	7,759,000,000
Private Equity Funds [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	578,000,000	578,000,000
Private Equity Funds [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	0	0
Private Equity Funds [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	6,831,000,000	7,181,000,000
Private Equity Funds [Member] | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	0	0
All other assets [Member] | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	8,744,000,000	8,699,000,000
All other assets [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	4,198,000,000	4,188,000,000
All other assets [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	561,000,000	253,000,000
All other assets [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	3,985,000,000	4,258,000,000
All other assets [Member] | Fair Value, Measurements, Recurring [Member] | Netting adjustments [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Total other assets	0	0
Long Term Beneficial Interests | Fair value | Fair Value, Measurements, Recurring [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Beneficial interests issued by consolidated VIEs, at fair value	1,130,000,000	1,170,000,000
FairValueLevelThreeToLevelTwoTransfersAmount [Member] | Asset-backed securities | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading assets	1,300,000,000
FairValueLevelThreeToLevelTwoTransfersAmount [Member] | Collateralized loan obligations | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Available-for-sale securities	27,300,000,000
FairValueLevelThreeToLevelTwoTransfersAmount [Member] | Equity | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets and liabilities measured at fair value on a recurring basis [Abstract]
Trading liabilities			$ 1,200,000,000