XML 14 R1.htm IDEA: XBRL DOCUMENT v3.24.0.1
Document and Entity Information - USD ($)
 12 Months Ended
Dec. 31, 2023
Feb. 16, 2024
Jun. 30, 2023
Cover [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2023    
Document Fiscal Year Focus 2023    
Document Fiscal Period Focus FY    
Entity Registrant Name Saia, Inc.    
Entity Central Index Key 0001177702    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer Yes    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Filer Category Large Accelerated Filer    
Entity Common Stock, Shares Outstanding   26,587,167  
Entity Public Float     $ 9,085,980,151
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Interactive Data Current Yes    
Entity File Number 0-49983    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 48-1229851    
Document Annual Report true    
Document Transition Report false    
Entity Address, Address Line One 11465 Johns Creek Parkway    
Entity Address, Address Line Two Suite 400    
Entity Address, City or Town Johns Creek    
Entity Address, State or Province GA    
Entity Address, Postal Zip Code 30097    
City Area Code 770    
Local Phone Number 232-5067    
Title of each class Common Stock, par value $.001 per share    
Security Exchange Name NASDAQ    
Trading Symbol SAIA    
ICFR Auditor Attestation Flag true    
Auditor Name KPMG LLP    
Auditor Location Atlanta, Georgia, United States    
Auditor Firm ID 185    
Documents Incorporated by Reference

Portions of the definitive Proxy Statement to be filed within 120 days of December 31, 2023, pursuant to Regulation 14A under the Securities Exchange Act of 1934 for the Annual Meeting of Stockholders to be held April 25, 2024, have been incorporated by reference into Part III of this Form 10-K.

    
Document Financial Statement Error Correction [Flag] false