Acquisitions - Narrative (Details) - USD ($) $ in Thousands				3 Months Ended
	Jan. 01, 2022	Oct. 01, 2021	Feb. 01, 2021	Mar. 31, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Goodwill				$ 347,423	$ 338,406
Contingent consideration on business acquisition				130,728	$ 162,564
AllianzGI
Business Acquisition [Line Items]
Annual payment term			7 years
Contingent consideration paid for an asset acquisition				33,000
Contingent consideration on asset acquisition				117,000
Stone Harbor Investment Partners, LLC
Business Acquisition [Line Items]
Purchase price	$ 29,400
Goodwill	8,846
Definite-lived intangible assets acquired	10,800
Expected tax deductible amount of goodwill acquired	$ 19,600
Period for expected tax deductible amount of goodwill	15 years
Payments to acquire businesses, gross	$ 28,200
Contingent consideration on business acquisition	$ 1,200
Westchester
Business Acquisition [Line Items]
Purchase price		$ 169,300
Goodwill		23,000
Expected tax deductible amount of goodwill acquired		$ 155,600
Period for expected tax deductible amount of goodwill		15 years
Payments to acquire businesses, gross		$ 156,800
Contingent consideration on business acquisition				$ 12,500
Intangible assets		$ 144,400