Investment and Other Income , Net - Schedule of Investment and Other Income, Net (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2024 |
Mar. 31, 2023 |
Mar. 31, 2024 |
Mar. 31, 2023 |
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| Other Income and Expenses [Abstract] | ||||
| Dividend and interest income | $ 38.0 | $ 32.3 | $ 92.8 | $ 68.8 |
| Gains (losses) on investments, net | (18.5) | 3.0 | 41.6 | 48.5 |
| Income from investments in equity method investees | 24.4 | 20.6 | 81.3 | 52.6 |
| Rental income | 10.9 | 13.4 | 21.7 | 24.0 |
| Foreign currency exchange losses, net | (1.3) | (6.5) | (8.7) | (33.6) |
| Other, net | (1.0) | (2.2) | (3.0) | (9.8) |
| Investment and other income, net | $ 52.5 | $ 60.6 | $ 225.7 | $ 150.5 |
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- Definition Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of realized and unrealized gain (loss) on investment. Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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- Definition Amount of income (loss) for proportionate share of equity method investee's income (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount of expense related to nonoperating activities, classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of income (expense) related to nonoperating activities, classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Income earned by providing the use of assets to an outside party in exchange for a payment or series of payments that is nonoperating in nature. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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