Investments - Schedule of Investment Components (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Investment Holdings [Line Items]
Total investments per Condensed Consolidated Balance Sheets	$ 53.4	$ 54.5
Realized and unrealized gains (losses) on other investments held at fair value \| Consolidated Entity Excluding Consolidated Funds
Investment Holdings [Line Items]
Investments, fair value disclosure	9.0	9.5
Investments related to long-term incentive compensation plans \| Consolidated Entity Excluding Consolidated Funds
Investment Holdings [Line Items]
Investments, fair value disclosure	$ 44.4	$ 45.0

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

+ References

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))
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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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