Investments - Additional Information (Detail) - USD ($) $ in Millions |
Mar. 31, 2025 |
Dec. 31, 2024 |
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| Schedule of Investments [Line Items] | ||
| Total investments | $ 174.0 | $ 177.4 |
| Partnership Interests in Private Equity Funds | ||
| Schedule of Investments [Line Items] | ||
| Total investments | 8.4 | 8.6 |
| Investments, fair value | 7.2 | 7.3 |
| Equity method investments, fair value | 1.2 | 1.3 |
| Seed Capital Investments [Member] | ||
| Schedule of Investments [Line Items] | ||
| Total investments | $ 23.0 | $ 23.1 |
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- Definition Fair value portion of investments accounted under the equity method. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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