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Goodwill and Acquired Client Relationships - Schedule of changes in and the components of acquired client relationships (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012
Net Book Value |  |
Total, Net book value balance at the beginning of the period | $ 1,585.5 | $ 1,321.1
Total, New investments | 0 | 452.6
Total, Amortization and Impairment | (128.2) | (200.0)
Total, Foreign currency translation | 3.4 | 11.8
Total, Transfers and other | 0 | 0
Total, Net book value balance at the end of the period | 1,460.7 | 1,585.5
Acquired client relationships [Member] |  |
Definite-lived |  |
Gross book value balance at the beginning of the period | 1,109.6 | 970.5
Accumulated amortization balance at the beginning of the period | (383.5) | (317.0)
Net book value balance at the beginning of the period | 726.1 | 653.5
New Investments | 0 | 131.1
Amortization and impairments | (128.2) | (97.8)
Foreign currency translation | (1.2) | 1.1
Gross Book Value, Definite-lived, Transfers and other | (68.9) | 6.9
Accumulated Amortization, Definite-lived, Transfers and other | 68.9 | 31.3
Net Book Value, Definite-lived, Transfers and other | 0 | 38.2
Gross book value balance at the end of the period | 1,039.5 | 1,109.6
Accumulated amortization balance at the end of the period | (442.8) | (383.5)
Net book value balance at the end of the period | 596.7 | 726.1
Indefinite-lived |  |
Net book value balance at the beginning of the period | 859.4 | 667.6
New investments | 0 | 321.5
Amortization and Impairment | 0 | (102.2)
Foreign currency translation | 4.6 | 10.7
Transfers and other | 0 | (38.2)
Net book value balance at the end of the period | $ 864.0 | $ 859.4

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