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Intangible Assets - Schedule of Changes in Goodwill (Details) $ in Millions		6 Months Ended
		Jun. 30, 2015 USD ($)
Goodwill [Roll Forward]
Beginning balance		$ 2,652.8
New investments	[1]	29.0
Foreign currency translation		(11.8)
Ending balance		2,670.0
Institutional
Goodwill [Roll Forward]
Beginning balance		1,159.1
New investments	[1]	1.6
Foreign currency translation		(13.3)
Ending balance		1,147.4
Mutual Fund
Goodwill [Roll Forward]
Beginning balance		1,125.3
New investments	[1]	0.0
Foreign currency translation		10.6
Ending balance		1,135.9
High Net Worth
Goodwill [Roll Forward]
Beginning balance		368.4
New investments	[1]	27.4
Foreign currency translation		(9.1)
Ending balance		$ 386.7
[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



-Topic 350



-SubTopic 20



-Section 50



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+ References

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