Acquisition (Details) (USD $)	Jul. 06, 2011	Jan. 18, 2011
Business Acquisition [Line Items]
Cash purchase consideration		$ 72,400,000
Indefinite-lived intangible assets purchase price allocation		52,600,000
Tangible net assets purchase price allocation		10,200,000
Deferred tax liabilities, purchase price allocation		(14,000,000)
Goodwill amount purchase price allocation		23,600,000
Assets Under Management at acquisition date	$ 10,900,000,000	$ 1,500,000,000

This element represents the value of assets under management acquired.

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- Definition

Amount of cash paid to acquire the entity.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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- Definition

The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

+ References

+ Details

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- Definition

Amount of deferred tax assets or liabilities for the differences between the values assigned and the tax bases of assets and liabilities in a business combination, net of any valuation allowance for deferred tax assets.

+ References

+ Details

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- Definition

Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 52
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 53
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

+ Details

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- Definition

The amount of acquisition cost of a business combination allocated to noncurrent assets of the acquired entity, except for property plant and equipment, intangible assets, and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph e
-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 Emerging Issues Task Force (EITF)
-Number 98-1
-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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 37
-Subparagraph f
-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.

+ Details

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