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Goodwill and Acquired Client Relationships - Additional Information (Details) - USD ($) | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Acquired Client Relationships |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |
Intangible impairments | $ 0 |
Acquired Client Relationships |  |
Intangible Assets |  |
Amortization and impairment expenses of intangible assets | 7,500,000 |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |
Finite-lived intangible, future amortization expense in 2021 | 23,000,000 |
Finite-lived intangible, future amortization expense in 2022 | 30,000,000 |
Finite-lived intangible, future amortization expense in 2023 | 30,000,000 |
Finite-lived intangible, future amortization expense in 2024 | 20,000,000 |
Finite-lived intangible, future amortization expense in 2025 | 20,000,000 |
Finite-lived intangible, future amortization expense in 2026 | 10,000,000 |
Intangible impairments | 0 |
Acquired Client Relationships | Intangible amortization and impairments |  |
Intangible Assets |  |
Amortization and impairment expenses of intangible assets | $ 7,500,000 | $ 20,600,000

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- Definition Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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