Annual report pursuant to Section 13 and 15(d)

Document And Entity Information

Document And Entity Information - USD ($)
12 Months Ended
Dec. 31, 2021
Feb. 21, 2022
Jun. 30, 2021
Cover [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2021    
Document Fiscal Year Focus 2021    
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   114,863,803  
Entity Public Float     $ 24,053,489,079
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Well-known Seasoned Issuer Yes    
ICFR Auditor Attestation Flag true    
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 2022 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