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Investments (Tables) | 9 Months Ended
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Sep. 30, 2025
Investments, Debt and Equity Securities [Abstract] |
Schedule of Investments in Marketable Securities | The following table summarizes the Company’s Investments:
|  | December 31, 2024 |  | September 30, 2025
Investments in marketable securities |  |  |  |
Equity securities |  | $32.3 |  | $37.1
Debt securities |  | 24.3 |  | 48.4
Total investments in marketable securities |  | 56.6 |  | 85.5
Other investments |  |  |  |
Investments measured at NAV as a practical expedient |  | $488.6 |  | $523.8
Investments without readily determinable fair values |  | 50.4 |  | 50.4
Total other investments |  | 539.0 |  | 574.2
Investments |  | $595.6 |  | $659.7
The following table summarizes the cost, gross unrealized gains, gross unrealized losses, and fair value of investments in equity securities:
|  | December 31, 2024 |  | September 30, 2025
Cost |  | $30.0 |  | $37.8
Unrealized gains |  | 3.7 |  | 7.9
Unrealized losses |  | (1.4) |  | (8.6)
Fair value |  | $32.3 |  | $37.1
The following table summarizes the cost, gross unrealized gains, gross unrealized losses, and fair value of investments in consolidated Affiliate sponsored investment products classified as trading:
|  | December 31, 2024 |  | September 30, 2025
Cost |  | $24.6 |  | $47.7
Unrealized gains |  | — |  | 1.0
Unrealized losses |  | (0.3) |  | (0.3)
Fair value |  | $24.3 |  | $48.4
Schedule of Other Investments and Unfunded Commitments | The following table summarizes the fair values of investments that are measured at net asset value (“NAV”) as a practical expedient and any related unfunded commitments:
| December 31, 2024 |  | September 30, 2025
| Fair Value |  | Unfunded Commitments |  | Fair Value |  | Unfunded Commitments
Investments with limited liquidity(1) | $486.9 |  | $205.5 |  | $474.8 |  | $240.6
Investments with periodic liquidity(2) | 1.7 |  | — |  | 49.0 |  | 24.7
Total(3) | $488.6 |  | $205.5 |  | $523.8 |  | $265.3
___________________________ (1)The Company expects to receive distributions related to its interests in investments with limited liquidity as the underlying assets are liquidated over the life of the investments, which is generally up to 15 years. The Company accounts for the majority of its interests in investments with limited liquidity one quarter in arrears (adjusted for current period calls and distributions). (2)Investments with periodic liquidity are generally redeemable on a daily, monthly, or quarterly basis. (3)Investments measured at NAV as a practical expedient primarily invest in a broad range of private markets. Fair value attributable to the controlling interest was $370.1 million and $405.2 million as of December 31, 2024 and September 30, 2025, respectively.
Schedule of Investments without Readily Determinable Fair Value | The following table summarizes the cost, cumulative unrealized gains, and carrying amount of the Company’s investment in a private corporation where it does not exercise significant influence, and does not have a readily determinable fair value:
| December 31, 2024 |  | September 30, 2025
Cost | $8.5 |  | $8.5
Cumulative unrealized gains | 41.9 |  | 41.9
Carrying amount | $50.4 |  | $50.4
The following tables present the changes in other investments:
|  | For the Three Months Ended September 30,
|  | 2024 |  | 2025
|  | Measured at NAV as a Practical Expedient |  | Without Readily Determinable Fair Values |  | Total |  | Measured at NAV as a Practical Expedient |  | Without Readily Determinable Fair Values |  | Total
Balance, beginning of period |  | $479.9 |  | $50.4 |  | $530.3 |  | $515.7 |  | $50.4 |  | $566.1
Purchases and commitments funded |  | 13.6 |  | — |  | 13.6 |  | 19.6 |  | — |  | 19.6
Sales and distributions |  | (20.4) |  | — |  | (20.4) |  | (25.4) |  | — |  | (25.4)
Net realized and unrealized gains |  | 9.3 |  | — |  | 9.3 |  | 13.9 |  | — |  | 13.9
Balance, end of period |  | $482.4 |  | $50.4 |  | $532.8 |  | $523.8 |  | $50.4 |  | $574.2
|  | For the Nine Months Ended September 30,
|  | 2024 |  | 2025
|  | Measured at NAV as a Practical Expedient |  | Without Readily Determinable Fair Values |  | Total |  | Measured at NAV as a Practical Expedient |  | Without Readily Determinable Fair Values |  | Total
Balance, beginning of period |  | $430.5 |  | $50.4 |  | $480.9 |  | $488.6 |  | $50.4 |  | $539.0
Purchases and commitments funded |  | 78.1 |  | — |  | 78.1 |  | 68.5 |  | — |  | 68.5
Sales and distributions |  | (47.1) |  | — |  | (47.1) |  | (67.3) |  | — |  | (67.3)
Net realized and unrealized gains |  | 20.9 |  | — |  | 20.9 |  | 34.0 |  | — |  | 34.0
Balance, end of period |  | $482.4 |  | $50.4 |  | $532.8 |  | $523.8 |  | $50.4 |  | $574.2

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