Segment and Related Information	3 Months Ended
Mar. 31, 2026
Segment Reporting [Abstract]
Segment and Related Information	NOTE H – Segment and Related Information The Company is a single reportable segment entity and derives its earnings primarily from financing or leasing of PACCAR products and services provided to truck customers and dealers in the United States. The Company’s chief operating decision maker is the Chief Executive Officer (CEO). The CEO evaluates the performance of the Company based on income before income taxes. The significant expenses reviewed by the CEO are consistent with those presented on the Company’s Statements of Comprehensive Income and Retained Earnings. Refer to the Company’s financial statements under this Part I, Item 1 for further information.

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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