Document And Entity Information - USD ($)	12 Months Ended
Document And Entity Information - USD ($)	Dec. 31, 2025	Feb. 17, 2026	Jun. 30, 2025
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2025
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Trading Symbol	ODFL
Entity Registrant Name	OLD DOMINION FREIGHT LINE, INC.
Entity Central Index Key	0000878927
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		208,425,619
Entity Public Float			$ 30,418,290,020
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Well-known Seasoned Issuer	Yes
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction [Flag]	false
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock ($0.10 par value)
Security Exchange Name	NASDAQ
Entity File Number	0-19582
Entity Incorporation, State or Country Code	VA
Entity Tax Identification Number	56-0751714
Entity Address, Address Line One	500 Old Dominion Way
Entity Address, City or Town	Thomasville
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27360
City Area Code	336
Local Phone Number	889-5000
Document Annual Report	true
Document Transition Report	false
Documents Incorporated by Reference	Certain portions of the Company’s Proxy Statement for the 2026 Annual Meeting of Shareholders are incorporated by reference into Part III of this report.
Auditor Name	Ernst & Young LLP
Auditor Location	Raleigh, North Carolina
Auditor Firm ID	42
Auditor Opinion [Text Block]	We have audited the accompanying balance sheets of Old Dominion Freight Line, Inc. (the Company) as of December 31, 2025 and 2024, the related statements of operations, changes in shareholders' equity and cash flows for each of the three years in the period ended December 31, 2025, and the related notes and the financial statement schedule listed in the Index at Item 15(a)(2) (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2025 and 2024, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2025, in conformity with U.S. generally accepted accounting principles. We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company's internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework), and our report dated February 24, 2026 expressed an unqualified opinion thereon.

OLD DOMINION FREIGHT LINE, INC. 10-K