Consolidated Investment Products - Schedule of Investments measured at NAV (Details) - USD ($) $ in Millions |
6 Months Ended | 12 Months Ended | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Mar. 31, 2023 |
Sep. 30, 2022 |
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Schedule Of Consolidated Investment Products [Line Items] | ||||||||||||
Unfunded commitments | $ 45.6 | $ 51.4 | ||||||||||
Nonredeemable investments with known liquidation periods | ||||||||||||
Schedule Of Consolidated Investment Products [Line Items] | ||||||||||||
Alternative Investment | [1] | $ 33.0 | $ 32.8 | |||||||||
Liquidation weighted-average period | 3 years 3 months 18 days | 3 years 4 months 24 days | ||||||||||
Nonredeemable investments with unknown liquidation periods | ||||||||||||
Schedule Of Consolidated Investment Products [Line Items] | ||||||||||||
Alternative Investment | [1] | $ 17.4 | $ 29.4 | |||||||||
Redeemable Funds | ||||||||||||
Schedule Of Consolidated Investment Products [Line Items] | ||||||||||||
Alternative Investment | [2] | 52.0 | 23.8 | |||||||||
CIPs [Member] | ||||||||||||
Schedule Of Consolidated Investment Products [Line Items] | ||||||||||||
Unfunded commitments | [3] | 0.0 | 0.2 | |||||||||
Unfunded commitments Company contractually obligated to fund | 0.1 | |||||||||||
CIPs [Member] | Nonredeemable investments with known liquidation periods | ||||||||||||
Schedule Of Consolidated Investment Products [Line Items] | ||||||||||||
Alternative Investment | [4] | 0.0 | 19.5 | |||||||||
CIPs [Member] | Nonredeemable investments with unknown liquidation periods | ||||||||||||
Schedule Of Consolidated Investment Products [Line Items] | ||||||||||||
Alternative Investment | [4] | 19.9 | 12.0 | |||||||||
CIPs [Member] | Redeemable Funds | ||||||||||||
Schedule Of Consolidated Investment Products [Line Items] | ||||||||||||
Alternative Investment | [5] | $ 126.5 | $ 142.0 | |||||||||
CIPs [Member] | Nonredeemable Private Debt, Equity and Infrastructure Funds [Member] | ||||||||||||
Schedule Of Consolidated Investment Products [Line Items] | ||||||||||||
Liquidation weighted-average period | 3 months 18 days | |||||||||||
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