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Intangible Assets - Schedule of Changes in Goodwill (Details) $ in Millions	9 Months Ended
	Sep. 30, 2015 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 2,652.8
New investments	29.0	[1]
Foreign currency translation	(34.5)
Ending balance	2,647.3
Institutional
Goodwill [Roll Forward]
Beginning balance	1,159.1
New investments	1.6	[1]
Foreign currency translation	(21.8)
Ending balance	1,138.9
Mutual Fund
Goodwill [Roll Forward]
Beginning balance	1,125.3
New investments	0.0	[1]
Foreign currency translation	0.7
Ending balance	1,126.0
High Net Worth
Goodwill [Roll Forward]
Beginning balance	368.4
New investments	27.4	[1]
Foreign currency translation	(13.4)
Ending balance	$ 382.4
[1] On April 1, 2015, the Company completed its investment in Baker Street Advisors, LLC.

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



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-SubTopic 20



-Section 50



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