Investments - Schedule of Investments (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Investments [Abstract]
Accrued performance allocations	$ 4,184.2	$ 3,855.6
Principal equity method investments, excluding performance allocations	1,699.4	2,443.6
Principal investments in CLOs and other	600.6	505.2
Total	$ 6,484.2	$ 6,804.4

Sum of the carrying amounts as of the balance sheet date of all investments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(h))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Name:	us-gaap_Investments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant