Goodwill and Acquired Client Relationships - Additional Information (Details) - Acquired Client Relationships - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Intangible Assets
Amortization and impairment expenses of intangible assets	$ 7.3	$ 12.5	$ 14.5	$ 25.0
Estimated Future Amortization Expense of Finite-Lived Intangibles
Finite-lived intangible, future amortization expense, remainder of fiscal year	15.0		15.0
Finite-lived intangible, future amortization expense in year one	25.0		25.0
Finite-lived intangible, future amortization expense in year two	25.0		25.0
Finite-lived intangible, future amortization expense in year three	25.0		25.0
Finite-lived intangible, future amortization expense in year four	25.0		25.0
Finite-lived intangible, future amortization expense in year five	$ 15.0		$ 15.0

-- None. No documentation exists for this element. --

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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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://www.xbrl.org/2003/role/exampleRef
-Topic 350
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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 remainder of current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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 fifth 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

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth 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

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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 third 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

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second 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).

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