Fair Value Measurements - Quantitative Information about Recurring Fair Value Measurement of Assets and Liabilities Classified as Level 3 (Detail) (USD $)	6 Months Ended		12 Months Ended
	Jun. 30, 2014		Dec. 31, 2013
Minimum [Member] | Collateralized debt obligations [Member] | Broker quotes or consensus pricing and, where applicable, discounted cash flows [Member] | Prepayment rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	1.00%		0.00%
Minimum [Member] | Collateralized debt obligations [Member] | Broker quotes or consensus pricing and, where applicable, discounted cash flows [Member] | Constant default rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	6.00%		5.00%
Minimum [Member] | Collateralized debt obligations [Member] | Broker quotes or consensus pricing and, where applicable, discounted cash flows [Member] | Loss Severity Rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	90.00%		90.00%
Minimum [Member] | Corporate and other domestic [Member] | Discounted cash flows [Member] | Spread volatility on collateral assets [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	1.00%		1.00%
Minimum [Member] | Foreign debt securities [Member] | Discounted cash flows [Member] | Correlations of default among a portfolio of credit names of embedded credit derivatives [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs			36.00%
Minimum [Member] | Interest rate contracts [Member] | Market comparable adjusted for probability to fund [Member] | Probability to fund for rate lock commitments [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	5.00%		10.00%
Minimum [Member] | Foreign exchange contracts [Member] | Option pricing model [Member] | Implied volatility of currency pairs [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	8.00%	[1]	11.00%	[1]
Minimum [Member] | Equity derivative contracts [Member] | Option pricing model [Member] | Equity / Equity Index volatility [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	9.00%	[1]	6.00%	[1]
Minimum [Member] | Equity derivative contracts [Member] | Option pricing model [Member] | Equity / Equity and Equity / Index correlation [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	52.00%	[1]	50.00%	[1]
Minimum [Member] | Credit contracts [Member] | Option pricing model [Member] | Correlation of defaults of a portfolio of reference credit names [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	49.00%		46.00%
Minimum [Member] | Credit contracts [Member] | Option pricing model [Member] | Issuer by issuer correlation of defaults [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	83.00%
Minimum [Member] | Credit Derivative Contracts [Member] | Option pricing model [Member] | Industry by industry correlation of defaults [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs			83.00%
Minimum [Member] | Mortgage servicing rights [Member] | Option adjusted discounted cash flows [Member] | Constant prepayment rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	8.00%		5.00%
Minimum [Member] | Mortgage servicing rights [Member] | Option adjusted discounted cash flows [Member] | Option adjusted spread [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	8.00%		8.00%
Minimum [Member] | Mortgage servicing rights [Member] | Option adjusted discounted cash flows [Member] | Estimated annualized costs to service [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of inputs per account	$ 91		$ 91
Minimum [Member] | Deposits In Domestic Offices [Member] | Option adjusted discounted cash flows [Member] | Equity / Equity Index volatility [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	9.00%	[1],[2]	6.00%	[1],[2]
Minimum [Member] | Deposits In Domestic Offices [Member] | Option adjusted discounted cash flows [Member] | Equity / Equity and Equity / Index correlation [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	47.00%		50.00%
Minimum [Member] | Deposits In Domestic Offices [Member] | Option adjusted discounted cash flows [Member] | Implied volatility of currency pairs [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	8.00%	[1],[2]	11.00%	[1],[2]
Minimum [Member] | Long-term Debt [Member] | Option adjusted discounted cash flows [Member] | Equity / Equity Index volatility [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	9.00%	[1],[2]	6.00%	[1],[2]
Minimum [Member] | Long-term Debt [Member] | Option adjusted discounted cash flows [Member] | Equity / Equity and Equity / Index correlation [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	47.00%	[1],[2]	50.00%	[1],[2]
Minimum [Member] | Long-term Debt [Member] | Option adjusted discounted cash flows [Member] | Implied volatility of currency pairs [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	8.00%	[1],[2]	11.00%	[1],[2]
Maximum [Member] | Collateralized debt obligations [Member] | Broker quotes or consensus pricing and, where applicable, discounted cash flows [Member] | Prepayment rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	5.00%		5.00%
Maximum [Member] | Collateralized debt obligations [Member] | Broker quotes or consensus pricing and, where applicable, discounted cash flows [Member] | Constant default rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	7.00%		7.00%
Maximum [Member] | Collateralized debt obligations [Member] | Broker quotes or consensus pricing and, where applicable, discounted cash flows [Member] | Loss Severity Rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	91.00%		100.00%
Maximum [Member] | Corporate and other domestic [Member] | Discounted cash flows [Member] | Spread volatility on collateral assets [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	3.00%		3.00%
Maximum [Member] | Foreign debt securities [Member] | Discounted cash flows [Member] | Correlations of default among a portfolio of credit names of embedded credit derivatives [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs			63.00%
Maximum [Member] | Interest rate contracts [Member] | Market comparable adjusted for probability to fund [Member] | Probability to fund for rate lock commitments [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	97.00%		99.00%
Maximum [Member] | Foreign exchange contracts [Member] | Option pricing model [Member] | Implied volatility of currency pairs [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	14.00%	[1]	16.00%	[1]
Maximum [Member] | Equity derivative contracts [Member] | Option pricing model [Member] | Equity / Equity Index volatility [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	41.00%	[1]	69.00%	[1]
Maximum [Member] | Equity derivative contracts [Member] | Option pricing model [Member] | Equity / Equity and Equity / Index correlation [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	54.00%	[1]	58.00%	[1]
Maximum [Member] | Credit contracts [Member] | Option pricing model [Member] | Correlation of defaults of a portfolio of reference credit names [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	56.00%		54.00%
Maximum [Member] | Credit contracts [Member] | Option pricing model [Member] | Issuer by issuer correlation of defaults [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	95.00%
Maximum [Member] | Credit Derivative Contracts [Member] | Option pricing model [Member] | Industry by industry correlation of defaults [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs			95.00%
Maximum [Member] | Mortgage servicing rights [Member] | Option adjusted discounted cash flows [Member] | Constant prepayment rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	46.00%		22.00%
Maximum [Member] | Mortgage servicing rights [Member] | Option adjusted discounted cash flows [Member] | Option adjusted spread [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	19.00%		19.00%
Maximum [Member] | Mortgage servicing rights [Member] | Option adjusted discounted cash flows [Member] | Estimated annualized costs to service [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of inputs per account	333		333
Maximum [Member] | Deposits In Domestic Offices [Member] | Option adjusted discounted cash flows [Member] | Equity / Equity Index volatility [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	41.00%	[1],[2]	69.00%	[1],[2]
Maximum [Member] | Deposits In Domestic Offices [Member] | Option adjusted discounted cash flows [Member] | Equity / Equity and Equity / Index correlation [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	60.00%		58.00%
Maximum [Member] | Deposits In Domestic Offices [Member] | Option adjusted discounted cash flows [Member] | Implied volatility of currency pairs [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	14.00%	[1],[2]	16.00%	[1],[2]
Maximum [Member] | Long-term Debt [Member] | Option adjusted discounted cash flows [Member] | Equity / Equity Index volatility [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	41.00%	[1],[2]	69.00%	[1],[2]
Maximum [Member] | Long-term Debt [Member] | Option adjusted discounted cash flows [Member] | Equity / Equity and Equity / Index correlation [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	60.00%	[1],[2]	58.00%	[1],[2]
Maximum [Member] | Long-term Debt [Member] | Option adjusted discounted cash flows [Member] | Implied volatility of currency pairs [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	14.00%	[1],[2]	16.00%	[1],[2]
Weighted Average [Member] | Corporate and other domestic [Member] | Discounted cash flows [Member] | Correlation between insurance claim shortfall and collateral value [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Range of Inputs	80.00%		80.00%
Recurring [Member] | Level 3 [Member] | Prepayment rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Prepayment rates		Prepayment rates
Recurring [Member] | Level 3 [Member] | Constant default rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Conditional default rates		Conditional default rates
Recurring [Member] | Level 3 [Member] | Loss Severity Rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Loss severity rates		Loss severity rates
Recurring [Member] | Level 3 [Member] | Spread volatility on collateral assets [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Spread volatility on collateral assets		Spread volatility on collateral assets
Recurring [Member] | Level 3 [Member] | Correlation between insurance claim shortfall and collateral value [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Correlation between insurance claim shortfall and collateral value		Correlation between insurance claim shortfall and collateral value
Recurring [Member] | Level 3 [Member] | Correlations of default among a portfolio of credit names of embedded credit derivatives [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs			Correlations of default among a portfolio of credit names of embedded credit derivatives
Recurring [Member] | Level 3 [Member] | Probability to fund for rate lock commitments [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Probability to fund for rate lock commitments		Probability to fund for rate lock commitments
Recurring [Member] | Level 3 [Member] | Implied volatility of currency pairs [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Implied volatility of currency pairs		Implied volatility of currency pairs
Recurring [Member] | Level 3 [Member] | Equity / Equity Index volatility [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Equity / Equity Index volatility	[1],[2]	Equity / Equity Index volatility
Recurring [Member] | Level 3 [Member] | Equity / Equity and Equity / Index correlation [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Equity / Equity and Equity / Index correlation	[1],[2]	Equity / Equity and Equity / Index correlation
Recurring [Member] | Level 3 [Member] | Correlation of defaults of a portfolio of reference credit names [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Correlation of defaults of a portfolio of reference credit names		Correlation of defaults of a portfolio of reference credit names
Recurring [Member] | Level 3 [Member] | Industry by industry correlation of defaults [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Issuer by issuer correlation of defaults		Industry by industry correlation of defaults
Recurring [Member] | Level 3 [Member] | Constant prepayment rates [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Constant prepayment rates		Constant prepayment rates
Recurring [Member] | Level 3 [Member] | Option adjusted spread [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Option adjusted spread		Option adjusted spread
Recurring [Member] | Level 3 [Member] | Estimated annualized costs to service [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Estimated annualized costs to service		Estimated annualized costs to service
Recurring [Member] | Level 3 [Member] | Implied volatility of currency pairs [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Implied volatility of currency pairs	[1],[2]	Implied volatility of currency pairs
Recurring [Member] | Level 3 [Member] | Broker quotes or consensus pricing and, where applicable, discounted cash flows [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Broker quotes or consensus pricing and, where applicable, discounted cash flows		Broker quotes or consensus pricing and, where applicable, discounted cash flows
Recurring [Member] | Level 3 [Member] | Discounted cash flows [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Discounted cash flows		Discounted cash flows
Recurring [Member] | Level 3 [Member] | Broker quotes or consensus pricing [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Discounted cash flows
Recurring [Member] | Level 3 [Member] | Market comparable adjusted for probability to fund [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Market comparable adjusted for probability to fund		Market comparable adjusted for probability to fund
Recurring [Member] | Level 3 [Member] | Option pricing model [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Option pricing model	[1]	Option pricing model
Recurring [Member] | Level 3 [Member] | Option adjusted discounted cash flows [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Inputs	Option adjusted discounted cash flows	[1],[2]	Option adjusted discounted cash flows
Recurring [Member] | Level 3 [Member] | Collateralized debt obligations [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Assets	260,000,000		254,000,000
Recurring [Member] | Level 3 [Member] | Corporate and other domestic [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Assets	2,819,000,000		2,260,000,000
Recurring [Member] | Level 3 [Member] | Foreign debt securities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Assets	0		121,000,000
Recurring [Member] | Level 3 [Member] | Interest rate contracts [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Assets	0		1,000,000
Recurring [Member] | Level 3 [Member] | Foreign exchange contracts [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Assets	0	[1]	95,000,000
Recurring [Member] | Level 3 [Member] | Equity derivative contracts [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Assets	59,000,000	[1]	3,000,000
Recurring [Member] | Level 3 [Member] | Credit contracts [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Assets	257,000,000	[1]	191,000,000
Recurring [Member] | Level 3 [Member] | Mortgage servicing rights [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Assets	186,000,000		227,000,000
Recurring [Member] | Level 3 [Member] | Deposits In Domestic Offices [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Liabilities	(2,257,000,000)	[1],[2]	(2,334,000,000)
Recurring [Member] | Level 3 [Member] | Long-term Debt [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Liabilities	$ (738,000,000)	[1],[2]	$ (900,000,000)

[1] We are the client-facing entity and we enter into identical but opposite derivatives to transfer the resultant risks to our affiliates. With the exception of counterparty credit risks, we are market neutral. The corresponding intra-group derivatives are presented as equity derivatives and foreign exchange derivatives in the table.

[2] Structured deposits and structured notes contain embedded derivative features whose fair value measurements contain significant Level 3 inputs.