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Goodwill and Acquired Client Relationships - Schedule of Changes in the Components of Acquired Client Relationships (Details) $ in Millions | 6 Months Ended
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Jun. 30, 2018 USD ($)
Total |
Beginning balance, net book value | $ 1,449.7
Ending balance, net book value | 1,393.3
Acquired Client Relationships |
Definite-lived |
Beginning balance, gross book value | 1,295.5
Beginning balance, accumulated amortization | (874.5)
Beginning balance, net book value | 421.0
Amortization and impairments | (46.4)
Foreign currency translation | (1.2)
Ending balance, gross book value | 1,294.3
Ending balance, accumulated amortization | (920.9)
Ending balance, net book value | 373.4
Indefinite-lived |
Beginning balance, net book value | 1,028.7
Intangible amortization and impairments | 0.0
Foreign currency translation | (8.8)
Ending balance, net book value | 1,019.9
Total |
Beginning balance, net book value | 1,449.7
Amortization and impairments | (46.4)
Foreign currency translation | (10.0)
Ending balance, net book value | $ 1,393.3

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