Goodwill and Other Intangible Assets (Changes in the Carrying Amount of Other Intangible Assets) (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Beginning balance			$ 2,593	$ 1,810
Acquisition of BIAM			27
Amortization	(50)	(46)	(99)	(80)
Amortization, Total			(98)	(77)
Foreign currency translation, net			92	(31)
Other	2	3	2	3
Ending balance	2,616	2,731	2,616	2,731
Intesa and MIFA [Member]
Acquisition of Intesa and MIFA		1,026		1,026
Intesa and MIFA [Member] \| Investment Servicing [Member]
Acquisition of Intesa and MIFA		1,026		1,026
Investment Servicing [Member]
Beginning balance			2,559	1,760
Amortization			(94)	(73)
Foreign currency translation, net			91	(29)
Ending balance	2,556	2,684	2,556	2,684
Investment Management [Member]
Beginning balance			34	50
Acquisition of BIAM			27
Amortization			(4)	(4)
Foreign currency translation, net			1	(2)
Other	2	3	2	3
Ending balance	$ 60	$ 47	$ 60	$ 47

The cost of asset management business allocated to an identifiable intangible asset, excluding goodwill.

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- Definition

The expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets.

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- Definition

The aggregate amount assigned to a major class of finite-lived intangible assets acquired either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 44
-Subparagraph a(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16265-109275

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph a(2)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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- Definition

Reflects increase (decrease) to the recorded value of indefinite-lived intangible assets for foreign currency translation adjustments and purchase accounting adjustments needed to revise the carrying amount of indefinite-lived intangible assets to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f,g)
-URI http://asc.fasb.org/extlink&oid=6905597&loc=d3e13816-109267

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 42, 45
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

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-Name Accounting Standards Codification
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- Definition

The net carrying amount as of the balance sheet date of other indefinite-lived and finite-lived intangible assets that are not separately presented on the statement of financial position.

+ Details

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