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Goodwill and Acquired Client Relationships - Schedule of Changes in Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Goodwill [Roll Forward]
Balance, beginning of period	$ 2,523.6	$ 2,648.7
Veritable Transaction	0.0	(136.5)
Foreign currency translation	(18.7)	16.5
Other	0.0	(5.1)
Balance, end of period	2,504.9	$ 2,523.6
Non-controlling interests
Goodwill [Roll Forward]
Veritable Transaction	$ (3.5)

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Goodwill Deconsolidated

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- Definition

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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Amount of foreign currency translation gain (loss) which increases (decreases) asset representing future economic benefit from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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Amount of increase (decrease) of asset representing future economic benefit from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized, classified as other.

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