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v3.21.2

Goodwill and Acquired Client Relationships - Schedule of Changes in the Components of Acquired Client Relationships (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Jun. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Total |  |  |  |  |
Beginning balance, net book value |  |  |  | $ 1,048,800,000 |
Intangible amortization and impairments | $ (8,900,000) | $ (31,900,000) |  | (25,300,000) | $ (133,400,000)
Ending balance, net book value | 1,018,200,000 |  |  | 1,018,200,000 |
Acquired Client Relationships |  |  |  |  |
Definite-lived |  |  |  |  |
Beginning balance, gross book value |  |  |  | 1,166,600,000 |
Beginning balance, accumulated amortization |  |  |  | (1,026,800,000) |
Beginning balance, net book value |  |  |  | 139,800,000 |
Intangible amortization and impairments |  |  |  | (25,300,000) |
Foreign currency translation, gross |  |  |  | (200,000) |
Foreign currency translation, accumulated amortization |  |  |  | 100,000 |
Foreign currency translation, net |  |  |  | (100,000) |
Ending balance, gross book value | 1,166,400,000 |  |  | 1,166,400,000 |
Ending balance, accumulated amortization | (1,052,000,000) |  |  | (1,052,000,000) |
Ending balance, net book value | 114,400,000 |  |  | 114,400,000 |
Indefinite-lived |  |  |  |  |
Beginning balance, net book value |  | $ 0 |  | 909,000,000.0 |
Intangible impairments |  |  | $ (60,300,000) | 0 |
Foreign currency translation |  |  |  | (5,200,000) |
Ending balance, net book value | 903,800,000 |  | $ 0 | 903,800,000 |
Total |  |  |  |  |
Beginning balance, net book value |  |  |  | 1,048,800,000 |
Intangible amortization and impairments |  |  |  | (25,300,000) |
Foreign currency translation |  |  |  | (5,300,000) |
Ending balance, net book value | $ 1,018,200,000 |  |  | $ 1,018,200,000 |

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