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Intangible Assets - Schedule of Changes in the Components of Acquired Client Relationships (Details) $ in Millions | 6 Months Ended
--- | ---
Jun. 30, 2015 USD ($)
Indefinite-lived |  |
Beginning balance, net |  | $ 1,088.3
New investments | [1] | 0.0
Amortization and impairments |  | 0.0
Foreign currency translation |  | 3.8
Ending balance, net |  | 1,092.1
Total |  |
Beginning balance, net |  | 1,778.4
New investments | [1] | 23.6
Amortization and impairments |  | (55.9)
Foreign currency translation |  | 3.7
Ending balance, net |  | 1,749.8
Acquired Client Relationships |  |
Definite-lived |  |
Beginning balance, gross |  | 1,255.1
Beginning balance, accumulated amortization |  | (565.0)
Beginning balance, net |  | 690.1
New investments | [1] | 23.6
Amortization and impairments |  | (55.9)
Foreign currency translation |  | (0.1)
Ending balance, gross |  | 1,278.6
Ending balance, accumulated amortization |  | (620.9)
Ending balance, net |  | $ 657.7
[1] | On April 1, 2015, the Company completed its investment in Baker Street Advisors, LLC.

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