Related Party Transactions - Due from Related Party, Investment in Related Party, and Related Party Revenues (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Related party transactions
Total amounts due for investment advisory fee receivables from related parties	$ 14.1	$ 7.6
Related party revenues	54.7	54.4	$ 60.2
Unconsolidated Funds
Related party transactions
Investment advisory fee receivable from unconsolidated Funds	14.1	7.6
Unconsolidated Funds \| Management fees
Related party transactions
Related party revenues	52.7	52.8	59.0
Unconsolidated Funds \| Performance fees collected (performance penalties paid)
Related party transactions
Related party revenues	$ 2.0	$ 1.6	$ 1.2

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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+ Details