Business Combinations - Summary of Preliminary Purchase Price Allocation (Details) - USD ($) $ in Thousands		3 Months Ended
	Mar. 01, 2020	Mar. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Goodwill		$ 789,807	$ 774,534
HCL
Business Acquisition [Line Items]
Cash and Cash Equivalents	$ 14,000
Other Current Assets	11,300
Goodwill	19,100
Intangible Assets	27,600
Other Long-Term Assets	9,800
Less: Liabilities Acquired	(26,900)
Less: Fair Value of Redeemable Noncontrolling Interest in Subsidiary	(34,500)
Total Purchase Price Consideration	20,400
Accounts receivable	4,600
Intangible assets recorded in connection with acquisition		$ 27,600
HCL | Customer Relationships
Business Acquisition [Line Items]
Intangible assets recorded in connection with acquisition	$ 20,300
Weighted-average useful life	9 years
HCL | Rights to Manage Fund Assets
Business Acquisition [Line Items]
Intangible assets recorded in connection with acquisition	$ 6,900
Weighted-average useful life	11 years