v3.25.2
Cover - shares
 6 Months Ended
Jun. 30, 2025
Jul. 28, 2025
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2025  
Document Transition Report false  
Entity File Number 001-31573  
Entity Registrant Name Medifast, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 13-3714405  
Entity Address, Address Line One 100 International Drive  
Entity Address, City or Town Baltimore  
Entity Address, State or Province MD  
Entity Address, Postal Zip Code 21202  
City Area Code 410  
Local Phone Number 581-8042  
Title of 12(b) Security Common Stock, par value $0.001 per share  
Trading Symbol MED  
Security Exchange Name NYSE  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   10,991,064
Entity Central Index Key 0000910329  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q2  
Amendment Flag false