Transactions with PACCAR and Affiliates - Additional Information (Detail) $ in Millions	Mar. 31, 2026 USD ($) Facility
Related Party Transaction [Line Items]
Required ratio of net earnings available for fixed charges to fixed charges	125.00%
Number of facilities leased by company \| Facility	5
Foreign Finance Affiliates
Related Party Transaction [Line Items]
Loans to foreign affiliates, upper limit \| $	$ 1,100.0

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.

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+ Details