Commercial paper and term notes.

No definition available.

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- Definition

Debt Disclosure [Line Items]

+ References

No definition available.

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- Definition

Debt instrument, initial borrowing capacity amount

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of unused borrowing capacity under the financing arrangement that is available to the entity as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The net effect of fair value hedges, unamortized discounts and unamortized debt issuance costs on commercial paper and term notes.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Line of credit facility expiration month and year.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-4

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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Balance Type:	credit
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- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-2

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
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-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

+ Details

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Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Borrowings and Credit Arrangements - Additional Information (Detail) € in Millions, R$ in Millions, $ in Millions, $ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2024 EUR (€)	Dec. 31, 2024 MXN ($)	Dec. 31, 2024 AUD ($)	Dec. 31, 2024 CAD ($)	Dec. 31, 2024 BRL (R$)	Aug. 31, 2021 MXN ($)
Debt Disclosure [Line Items]
Interest paid on borrowings	$ 571.8	$ 396.5	$ 169.1
Line of credit, maximum capacity	5,478.7
Line of credit, unused borrowing capacity	4,956.5
Syndicated loan facility
Debt Disclosure [Line Items]
Line of credit, maximum capacity	4,000.0
Line of credit, outstanding amount	0.0
Expires in June 2024 \| Syndicated loan facility
Debt Disclosure [Line Items]
Line of credit, maximum capacity	$ 1,500.0
Line of credit, expiry date	2025-06
Expires in June 2026 \| Syndicated loan facility
Debt Disclosure [Line Items]
Line of credit, maximum capacity	$ 1,250.0
Line of credit, expiry date	2027-06
Expires in June 2028 \| Syndicated loan facility
Debt Disclosure [Line Items]
Line of credit, maximum capacity	$ 1,250.0
Line of credit, expiry date	2029-06
PACCAR's U.S. finance subsidiary \| Medium-term Notes
Debt Disclosure [Line Items]
Debt outstanding	$ 7,250.0
PACCAR's Brazilian finance subsidiary \| Medium-term Notes
Debt Disclosure [Line Items]
Debt outstanding \| R$								R$ 1,145.9
Debt, borrowing capacity \| R$								2,597.9
PACCAR's Brazilian Subsidiaries Letra Financeira Program \| Medium-term Notes
Debt Disclosure [Line Items]
Debt outstanding \| R$								R$ 500.0
PACCAR's European finance subsidiary \| Medium-term Notes
Debt Disclosure [Line Items]
Debt, unused borrowing capacity \| €				€ 597.9
Debt, borrowing capacity \| €				€ 2,500.0
PACCAR's Mexico finance subsidiary \| Commercial Paper
Debt Disclosure [Line Items]
Maximum limit of borrowing capacity									$ 5,000.0
PACCAR's Mexico finance subsidiary \| Medium-term Notes
Debt Disclosure [Line Items]
Debt, unused borrowing capacity					$ 5,570.0
PACCAR's Mexico finance subsidiary \| Medium-term Notes \| Commercial Paper
Debt Disclosure [Line Items]
Debt, borrowing capacity									$ 10,000.0
PACCAR's Australian subsidiary \| Medium-term Notes
Debt Disclosure [Line Items]
Debt outstanding						$ 700.0
PACCAR Canadian subsidiary \| Medium-term Notes
Debt Disclosure [Line Items]
Debt outstanding							$ 0
Financial Services
Debt Disclosure [Line Items]
Commercial paper and term notes borrowings	15,376.1	13,693.5
Fair value hedges and unamortized discounts, net	$ (51.7)	$ (54.1)