Credit Arrangements - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)
Line of Credit Facility [Line Items]
Credit facility available amount	$ 4,000.0
Company and PACCAR and Certain non-U.S. PACCAR Financial Subsidiaries
Line of Credit Facility [Line Items]
Credit facility available amount	3,088.0
PACCAR and Certain non-U.S. PACCAR Financial Subsidiaries
Line of Credit Facility [Line Items]
Credit facility available amount	912.0
Committed bank facility
Line of Credit Facility [Line Items]
Line of credit, maximum capacity	$ 4,000.0
Line of credit facility participation date	Dec. 31, 2024
Committed bank facility \| Matures in June 2024
Line of Credit Facility [Line Items]
Line of credit, maximum capacity	$ 1,500.0
Line of credit, maturity date	2025-06
Committed bank facility \| Matures in June 2026
Line of Credit Facility [Line Items]
Line of credit, maximum capacity	$ 1,250.0
Line of credit, maturity date	2027-06
Committed bank facility \| Matures in June 2028
Line of Credit Facility [Line Items]
Line of credit, maximum capacity	$ 1,250.0
Line of credit, maturity date	2029-06

PACCAR FINANCIAL CORP 10-K