FAIR VALUE MEASUREMENT (Details 4) (USD $)	9 Months Ended
	Sep. 30, 2012 correlation
Derivatives, liabilities
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	$ 0
Level 3 | Interest-bearing deposits | Internal Model
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of liabilities as of the balance sheet date	761,000,000
Level 3 | Interest-bearing deposits | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Equity Volatility	11.32%
Equity Forward	98.60%
Equity-Equity Correlation	0.6300
Equity-IR Correlation	0.2350
Forward Price	0.3745
Level 3 | Interest-bearing deposits | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Equity Volatility	72.70%
Equity Forward	111.10%
Equity-Equity Correlation	0.9800
Equity-IR Correlation	0.4900
Forward Price	1.1213
Level 3 | Federal funds purchased and securities loaned or sold under agreements to repurchase
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of liabilities as of the balance sheet date	841,000,000
Level 3 | Federal funds purchased and securities loaned or sold under agreements to repurchase | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Interest Rate (as a percent)	0.23%
Level 3 | Federal funds purchased and securities loaned or sold under agreements to repurchase | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Interest Rate (as a percent)	5.18%
Level 3 | Short-term borrowings and long-term debt | Price-based | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Equity Forward	77.00%
Level 3 | Short-term borrowings and long-term debt | Price-based | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Equity Forward	110.10%
Level 3 | Short-term borrowings and long-term debt | Yield Analysis | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 0.44
IR Volatility (as a percent)	0.10%
Equity-Equity Correlation	0.1000
Level 3 | Short-term borrowings and long-term debt | Yield Analysis | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 103.05
IR Volatility (as a percent)	0.63%
Equity-Equity Correlation	0.9990
Level 3 | Short-term borrowings and long-term debt | Internal Model
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of liabilities as of the balance sheet date	6,669,000,000
Level 3 | Short-term borrowings and long-term debt | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Equity Volatility	12.50%
Level 3 | Short-term borrowings and long-term debt | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Equity Volatility	44.70%
Level 3 | Federal funds sold and securities borrowed or purchased under agreements to resell
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	4,677,000,000
Level 3 | Federal funds sold and securities borrowed or purchased under agreements to resell | Cash flow | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Interest Rate (as a percent)	0.97%
Level 3 | Federal funds sold and securities borrowed or purchased under agreements to resell | Cash flow | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Interest Rate (as a percent)	1.39%
Level 3 | Loans | Price-based
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	4,917,000,000
Level 3 | Loans | Price-based | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 0.44
Level 3 | Loans | Price-based | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 103.05
Level 3 | Loans | Yield Analysis | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Credit Spread (as a percent)	0.00%
Level 3 | Loans | Yield Analysis | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Credit Spread (as a percent)	7.23%
Level 3 | Loans | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Future Evolution of NAV	0.00
Level 3 | Loans | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Future Evolution of NAV	100.00
Level 3 | Mortgage servicing rights | Cash flow
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	1,920,000,000
Level 3 | Mortgage servicing rights | Cash flow | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	0.00%
Prepayment period	2 years 2 months 12 days
Level 3 | Mortgage servicing rights | Cash flow | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	38.10%
Prepayment period	7 years 6 months
Level 3 | Interest rate contracts | Derivatives, assets | Cash flow | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Interest Rate (as a percent)	0.00%
Yield (as a percent)	0.05%
Credit Spread (as a percent)	0.00%
Mean Reversion	20.00%
Level 3 | Interest rate contracts | Derivatives, assets | Cash flow | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Interest Rate (as a percent)	13.00%
Yield (as a percent)	3.00%
Credit Spread (as a percent)	7.50%
Mean Reversion	20.00%
Level 3 | Interest rate contracts | Derivatives, assets | Internal Model
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	4,482,000,000
Level 3 | Interest rate contracts | Derivatives, assets | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
IR Volatility (as a percent)	0.10%
Level 3 | Interest rate contracts | Derivatives, assets | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
IR Volatility (as a percent)	100.00%
Level 3 | Foreign exchange contracts | Derivatives, assets | Internal Model
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	2,052,000,000
Level 3 | Foreign exchange contracts | Derivatives, assets | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Recovery Rate (as a percent)	20.00%
IR Volatility (as a percent)	0.10%
FX Volatility (as a percent)	2.00%
IR-FX Correlation	0.0040
FX-Credit Correlation	0.6500
Level 3 | Foreign exchange contracts | Derivatives, assets | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Recovery Rate (as a percent)	40.00%
IR Volatility (as a percent)	0.63%
FX Volatility (as a percent)	51.02%
IR-FX Correlation	0.6000
FX-Credit Correlation	1.0000
Level 3 | Equity contracts | Derivatives, assets | Cash flow | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 0.00
Equity Forward	77.00%
Equity-Equity Correlation	0.1000
Equity-IR Correlation	0.2350
Level 3 | Equity contracts | Derivatives, assets | Cash flow | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 36,109.13
Equity Forward	111.10%
Equity-Equity Correlation	0.9990
Equity-IR Correlation	0.4900
Level 3 | Equity contracts | Derivatives, assets | Internal Model
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	4,747,000,000
Level 3 | Equity contracts | Derivatives, assets | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Equity Volatility	3.86%
Level 3 | Equity contracts | Derivatives, assets | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Equity Volatility	113.83%
Level 3 | Commodity contracts | Derivatives, assets | Internal Model
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	2,694,000,000
Level 3 | Commodity contracts | Derivatives, assets | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Forward Price	0.3745
Commodity Correlation	(0.7700)
Commodity Volatility (as a percent)	5.00%
Level 3 | Commodity contracts | Derivatives, assets | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Forward Price	1.1213
Commodity Correlation	0.9500
Commodity Volatility (as a percent)	136.00%
Level 3 | Credit derivatives | Derivatives, assets | Price-based | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Credit Spread (as a percent)	0.00%
Recovery Rate (as a percent)	9.00%
Credit Correlation	0.0500
Upfront points	3.50
Level 3 | Credit derivatives | Derivatives, assets | Price-based | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Credit Spread (as a percent)	29.80%
Recovery Rate (as a percent)	78.00%
Credit Correlation	0.9500
Upfront points	100.00
Level 3 | Credit derivatives | Derivatives, assets | Internal Model
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	8,618,000,000
Level 3 | Credit derivatives | Derivatives, assets | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 0.00
Level 3 | Credit derivatives | Derivatives, assets | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 124.78
Level 3 | Nontrading derivatives and other financial assets and liabilities measured on a recurring basis (gross) | Derivatives | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Redemption Rate (as a percent)	30.62%
Level 3 | Nontrading derivatives and other financial assets and liabilities measured on a recurring basis (gross) | Derivatives | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Redemption Rate (as a percent)	99.50%
Level 3 | Nontrading derivatives and other financial assets and liabilities measured on a recurring basis (gross) | Derivatives | Comparables Analysis
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	2,668,000,000
Level 3 | Nontrading derivatives and other financial assets and liabilities measured on a recurring basis (gross) | Derivatives | Comparables Analysis | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 100.00
Level 3 | Nontrading derivatives and other financial assets and liabilities measured on a recurring basis (gross) | Derivatives | Comparables Analysis | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 100.00
Level 3 | Mortgage-backed securities | Trading and investment securities | Cash flow | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	0.00%
Level 3 | Mortgage-backed securities | Trading and investment securities | Cash flow | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	27.88%
Level 3 | Mortgage-backed securities | Trading and investment securities | Price-based
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	5,872,000,000
Level 3 | Mortgage-backed securities | Trading and investment securities | Price-based | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 0.00
Level 3 | Mortgage-backed securities | Trading and investment securities | Price-based | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 122.69
Level 3 | Equity securities | Trading and investment securities | Cash flow
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	1,301,000,000
Level 3 | Equity securities | Trading and investment securities | Cash flow | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	9.00%
Level 3 | Equity securities | Trading and investment securities | Cash flow | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	10.00%
Level 3 | Equity securities | Trading and investment securities | Price-based | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 0.00
Level 3 | Equity securities | Trading and investment securities | Price-based | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 650.00
Level 3 | Asset-backed securities | Trading and investment securities | Cash flow | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	0.00%
Weighted Average Life (WAL)	2.1
Level 3 | Asset-backed securities | Trading and investment securities | Cash flow | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	29.72%
Weighted Average Life (WAL)	24.8
Level 3 | Asset-backed securities | Trading and investment securities | Price-based
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	8,474,000,000
Level 3 | Asset-backed securities | Trading and investment securities | Price-based | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 0.00
Level 3 | Asset-backed securities | Trading and investment securities | Price-based | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 128.64
Level 3 | State and municipal, foreign government, corporate, and other debt securities | Trading and investment securities | Price-based
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	6,661,000,000
Level 3 | State and municipal, foreign government, corporate, and other debt securities | Trading and investment securities | Price-based | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 0.00
Level 3 | State and municipal, foreign government, corporate, and other debt securities | Trading and investment securities | Price-based | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 159.63
Level 3 | State and municipal, foreign government, corporate, and other debt securities | Trading and investment securities | Yield Analysis | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	0.00%
Level 3 | State and municipal, foreign government, corporate, and other debt securities | Trading and investment securities | Yield Analysis | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	30.00%
Level 3 | State and municipal, foreign government, corporate, and other debt securities | Trading and investment securities | Internal Model | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Credit Spread (as a percent)	0.00%
Level 3 | State and municipal, foreign government, corporate, and other debt securities | Trading and investment securities | Internal Model | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Credit Spread (as a percent)	7.23%
Level 3 | State and municipal, foreign government, corporate, and other debt securities | Trading and investment securities | Comparables Analysis | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Recovery Rate (as a percent)	0.00%
Level 3 | State and municipal, foreign government, corporate, and other debt securities | Trading and investment securities | Comparables Analysis | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Recovery Rate (as a percent)	100.00%
Level 3 | Non-marketable equity securities | Trading and investment securities | Cash flow | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
EBITDA multiples	4
Price-to-book ratio	0.9
Cost of capital	8.50%
Level 3 | Non-marketable equity securities | Trading and investment securities | Cash flow | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
EBITDA multiples	14.50
Price-to-book ratio	1.56
Cost of capital	25.00%
Level 3 | Non-marketable equity securities | Trading and investment securities | Price-based
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of assets as of the balance sheet date	4,784,000,000
Level 3 | Non-marketable equity securities | Trading and investment securities | Price-based | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Discount to price	$ 0.00
Level 3 | Non-marketable equity securities | Trading and investment securities | Price-based | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Discount to price	$ 36.00
Level 3 | Non-marketable equity securities | Trading and investment securities | Comparables Analysis | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Fund NAV	0.00
Level 3 | Non-marketable equity securities | Trading and investment securities | Comparables Analysis | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Fund NAV	310,794,142
Level 3 | Securities sold, not yet purchased | Trading account liabilities | Cash flow | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	0.00%
Weighted Average Life (WAL)	2.1
Level 3 | Securities sold, not yet purchased | Trading account liabilities | Cash flow | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Yield (as a percent)	21.54%
Weighted Average Life (WAL)	24.8
Level 3 | Securities sold, not yet purchased | Trading account liabilities | Price-based
Fair Value Inputs Assets Liabilities Quantitative Information
Fair value of liabilities as of the balance sheet date	$ 125,000,000
Level 3 | Securities sold, not yet purchased | Trading account liabilities | Price-based | Minimum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 0.00
Level 3 | Securities sold, not yet purchased | Trading account liabilities | Price-based | Maximum
Fair Value Inputs Assets Liabilities Quantitative Information
Price	$ 500.00