Investments - Components of Investments (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Investment Holdings [Line Items]
Investments at fair value	$ 54.5	$ 88.0
Equity-accounted investment in Affiliate	0.0	2.0
Total investments per Consolidated Balance Sheets	54.5	90.0
Consolidated Entity Excluding Consolidated Funds
Investment Holdings [Line Items]
Investments at fair value	54.5	88.0
Total investments per Consolidated Balance Sheets	54.5	90.0
Other investments held at fair value \| Consolidated Entity Excluding Consolidated Funds
Investment Holdings [Line Items]
Investments at fair value	9.5	40.0
Investments related to long-term incentive compensation plans held at fair value \| Consolidated Entity Excluding Consolidated Funds
Investment Holdings [Line Items]
Investments at fair value	$ 45.0	$ 48.0

Equity-Accounted Investments In Affiliates And Consolidated Funds

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+ References

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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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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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