Other Assets-Seed Capital and Private Equity Investments Valued Using Net Asset Value (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2014		Dec. 31, 2013
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Line Items]
Fair value	$ 418		$ 361
Unfunded commitments	41		54
Federal Reserve Bank stock	441		441
Seed capital and other funds
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Line Items]
Fair value	332	[1]	275	[1]
Unfunded commitments	12	[1]	23	[1]
Redemption frequency	Monthly-yearly	[1]	Monthly-yearly	[1]
Redemption notice period	3-45 days	[1]	3-45 days	[1]
Private equity funds
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Line Items]
Fair value	86	[2]	86	[2]
Unfunded commitments	$ 29	[2]	$ 31	[2]
Minimum
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Line Items]
Redemption notice period	P3D		P3D
Maximum
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Line Items]
Redemption notice period	P45D		P45D

[1] Other funds include various market neutral, leveraged loans, hedge funds, real estate and structured credit funds. Redemption notice periods vary by fund.

[2] Private equity funds primarily include numerous venture capital funds that invest in various sectors of the economy. Private equity funds do not have redemption rights. Distributions from such funds will be received as the underlying investments in the funds are liquidated.