v3.26.1
Fair Value Measurements - Schedule of Fair Value Measurements (Details) - EBP 002 - USD ($)
Dec. 31, 2025
Dec. 31, 2024
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value $ 2,321,276,526 $ 2,104,436,481
Mutual Funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 993,389,388 817,445,456
Old Dominion Freight Line, Inc. Common Stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 453,993,043 547,228,495
Self-directed Brokerage Accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 16,610,569 14,667,567
Collective Trust Funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 524,820,970 444,858,629
Pooled Separate Accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 332,462,556 280,236,334
Level 1    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 1,463,993,000 1,379,341,518
Level 1 | Mutual Funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 993,389,388 817,445,456
Level 1 | Old Dominion Freight Line, Inc. Common Stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 453,993,043 547,228,495
Level 1 | Self-directed Brokerage Accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 16,610,569 14,667,567
Level 2    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 0 0
Level 2 | Mutual Funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 0 0
Level 2 | Old Dominion Freight Line, Inc. Common Stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 0 0
Level 2 | Self-directed Brokerage Accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 0 0
Level 3    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 0 0
Level 3 | Mutual Funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 0 0
Level 3 | Old Dominion Freight Line, Inc. Common Stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 0 0
Level 3 | Self-directed Brokerage Accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 0 0
Level 1, 2 and 3    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 1,463,993,000 1,379,341,518
Level 1, 2 and 3 | Mutual Funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 993,389,388 817,445,456
Level 1, 2 and 3 | Old Dominion Freight Line, Inc. Common Stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 453,993,043 547,228,495
Level 1, 2 and 3 | Self-directed Brokerage Accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 16,610,569 14,667,567
Investments Measured at NAV | Collective Trust Funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value 524,820,970 444,858,629
Investments Measured at NAV | Pooled Separate Accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total investments at fair value $ 332,462,556 $ 280,236,334