Marketable Debt Securities Continuous Unrealized Losses (Detail) - Truck, Parts and Other - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Schedule Of Available For Sale Securities [Line Items] | ||
| Less than 12 Months Fair Value | $ 2,775.6 | $ 298.5 |
| Less than 12 Months Unrealized Losses | 48.5 | 1.0 |
| 12 Months or Greater Fair value | 26.5 | 75.5 |
| 12 Months or Greater Unrealized losses | $ 0.3 | $ 0.7 |
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset. Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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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. No definition available.
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- Details
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