Notional and Fair Value Amounts of Client-related and Trading Derivative Financial Instruments (Detail) (Client Related and Trading, USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Derivative [Line Items]
Notional Value	$ 275,071.3	$ 248,136.7
Fair Value Asset	4,233.0	2,967.5
Fair Value Liability	4,221.4	2,963.2
Foreign Exchange Contracts
Derivative [Line Items]
Notional Value	270,022.4	243,135.0
Fair Value Asset	4,132.8	2,844.7
Fair Value Liability	4,125.5	2,846.2
Interest Rate Contracts
Derivative [Line Items]
Notional Value	5,048.9	5,001.7
Fair Value Asset	100.2	122.8
Fair Value Liability	$ 95.9	$ 117.0

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226000-175313

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