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Impairment of Intangible Assets, Indefinite-Lived (Excluding Goodwill), Controlling Interest

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Amount of amortization expense for finite-lived intangible asset 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). Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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Amount of amortization expense for finite-lived intangible asset 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). Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Goodwill and Acquired Client Relationships - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended				6 Months Ended
	Jun. 30, 2026	Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025
Estimated Future Amortization Expense of Finite-Lived Intangibles
Impairment assessment assumptions, long-term revenue growth rates					0.00%
Impairment assessment assumptions, discount rates			10.50%		11.00%
Gain from affiliate transaction		$ 14.6		$ 0.0		$ 14.6	$ 0.0
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| MyCIO Wealth Partners, LLC
Estimated Future Amortization Expense of Finite-Lived Intangibles
Client assets	$ 5,600.0	5,600.0				5,600.0
Cash consideration	24.5	24.5				24.5
Gain from affiliate transaction	14.6
Acquired Client Relationships For Certain Mutual Fund Assets
Estimated Future Amortization Expense of Finite-Lived Intangibles
Amortization of intangible assets, noncontrolling interest			$ 30.5		$ 59.2
Intangible impairment			$ 43.0		70.0
Acquired Client Relationships, Mutual Fund Product
Estimated Future Amortization Expense of Finite-Lived Intangibles
Amortization of intangible assets, noncontrolling interest					4.0
Intangible impairment					7.0
Carrying value of intangible assets					$ 0.0
Minimum
Estimated Future Amortization Expense of Finite-Lived Intangibles
Impairment assessment assumptions, revenue growth rates					(21.00%)
Maximum
Estimated Future Amortization Expense of Finite-Lived Intangibles
Impairment assessment assumptions, revenue growth rates					0.00%
Acquired Client Relationships
Intangible Assets
Amortization and impairment expenses of intangible assets		7.2		$ 6.3		13.5	$ 12.6
Estimated Future Amortization Expense of Finite-Lived Intangibles
Intangible future amortization expense remainder of fiscal year	15.0	15.0				15.0
Intangible future amortization expense in year one	25.0	25.0				25.0
Intangible future amortization expense in year two	25.0	25.0				25.0
Intangible future amortization expense in year three	15.0	15.0				15.0
Intangible future amortization expense in year four	10.0	10.0				10.0
Intangible future amortization expense in year five	$ 10.0	$ 10.0				$ 10.0