Revenue - Schedule of Disaggregation of Revenue (Details) - Management fees - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Disaggregation of Revenue [Line Items]
Revenue:	$ 90.6	$ 102.2
Quant & Solutions \| U.S.
Disaggregation of Revenue [Line Items]
Revenue:	67.9	77.0
Quant & Solutions \| Non-U.S.
Disaggregation of Revenue [Line Items]
Revenue:	$ 22.7	$ 25.2

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details