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Intangible Assets Schedule of changes in and the components of acquired client relationships (Details) (USD $) In Millions, unless otherwise specified |  |  | 3 Months Ended
--- | --- | --- | ---
Mar. 31, 2014 | Dec. 31, 2013 | Mar. 31, 2014 Acquired client relationships [Member]
Definite-lived |  |  |
Beginning balance, Gross Book Value |  |  | $ 1,039.5
Beginning balance, Accumulated Amortization |  |  | (442.8)
Beginning balance, Net Book Value |  |  | 596.7
New Investments, Gross Book Value |  |  | 81.5
Amortization and impairments, Gross Book Value |  |  | (27.4)
Foreign currency translation, Gross Book Value |  |  | (0.7)
Ending balance, Gross Book Value |  |  | 1,120.3
Ending balance, Accumulated Amortization |  |  | (470.2)
Ending balance, Net Book Value |  |  | 650.1
Indefinite-lived |  |  |
Beginning balance, Net Book Value |  |  | 864.0
New Investments, Net Book Value |  |  | 45.4
Amortization and impairments, Net Book Value |  |  | 0
Foreign currency translation, Net Book Value |  |  | 1.6
Ending balance, Net Book Value |  |  | 911.0
Total |  |  |
Beginning balance, Net Book Value | 1,561.1 | 1,460.7 | 1,460.7
New Investments, Net Book Value |  |  | 126.9
Amortization and impairments, Net Book Value |  |  | (27.4)
Foreign currency translation, Net Book Value |  |  | 0.9
Ending balance, Net Book Value | $ 1,561.1 | $ 1,460.7 | $ 1,561.1

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