Equity Securities - (Summary of Investments in Equity Securities, by Classification) (Detail) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Investments, Debt and Equity Securities [Abstract] | ||
| Marketable equity securities | $ 505.4 | $ 477.6 |
| Non-marketable equity securities | 216.6 | 253.1 |
| Equity method investments | 146.1 | 118.4 |
| Equity Securities | $ 868.1 | $ 849.1 |
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- Definition The total of marketable equity securities, non-marketable equity securities and equity method investments. No definition available.
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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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