Investments - Principal Investments in CLOs and Other Investments (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
TCG BDC, Inc.
Debt and Equity Securities, FV-NI [Line Items]
Trading securities	$ 98.8	$ 81.7
CLO Senior and Subordinated Notes and Derivative Instruments
Debt and Equity Securities, FV-NI [Line Items]
Trading securities	$ 494.6	$ 532.6

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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