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Intangible Assets - Schedule of Changes in Goodwill (Details) $ in Millions	9 Months Ended
	Sep. 30, 2016 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 2,668.4
Foreign currency translation	(24.1)
Ending balance	2,644.3
Institutional
Goodwill [Roll Forward]
Beginning balance	1,141.3
Foreign currency translation	(0.6)
Ending balance	1,140.7
Mutual Fund
Goodwill [Roll Forward]
Beginning balance	1,119.5
Foreign currency translation	(26.9)
Ending balance	1,092.6
High Net Worth
Goodwill [Roll Forward]
Beginning balance	407.6
Foreign currency translation	3.4
Ending balance	$ 411.0

X

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	instant

X

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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X

- Definition

Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ 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)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Details

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X

- Details

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X

- Details

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