Intangible Assets - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Indefinite-lived Intangible Assets [Line Items]
Impairment of Intangible Asset	$ 0	$ 31,520,000	$ 0
Amortization expense for finite-lived intangible assets	13,900,000	12,500,000	$ 13,800,000
Finite-lived intangible assets, foreign currency translation	2,500,000
Goodwill, period increase (decrease)	6,700,000
Rights to Manage Fund Assets
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	304,600,000	295,600,000
Trade Name
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	50,100,000	$ 47,600,000
Right to Manage Public Funds
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	$ 158,600,000