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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.

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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 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).

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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 remainder of current fiscal year.

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No definition available.

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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 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).

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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).

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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 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).

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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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Equity Method Investments in Affiliates - Additional Information (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($) affiliate	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) affiliate	Sep. 30, 2022 USD ($)	Dec. 31, 2022 affiliate
Estimated Future Amortization Expense of Finite-Lived Intangibles
Number of affiliates \| affiliate	21		21		20
Acquired Client Relationships
Schedule of Equity Method Investments [Line Items]
Amortization of Intangible Assets			$ 37.5
Estimated Future Amortization Expense of Finite-Lived Intangibles
Finite-lived intangible, future amortization expense, remainder of fiscal year	$ 11.0		11.0
Finite-lived intangible, future amortization expense in year one	30.0		30.0
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	25.0		25.0
Equity Method Investee \| Acquired Client Relationships
Schedule of Equity Method Investments [Line Items]
Amortization of Intangible Assets	21.2	$ 31.4	63.0	$ 89.3
Estimated Future Amortization Expense of Finite-Lived Intangibles
Finite-lived intangible, future amortization expense, remainder of fiscal year	23.0		23.0
Finite-lived intangible, future amortization expense in year one	60.0		60.0
Finite-lived intangible, future amortization expense in year two	60.0		60.0
Finite-lived intangible, future amortization expense in year three	50.0		50.0
Finite-lived intangible, future amortization expense in year four	50.0		50.0
Finite-lived intangible, future amortization expense in year five	$ 40.0		$ 40.0