v3.26.1
Document and Entity Information - shares
3 Months Ended
Mar. 31, 2026
Apr. 30, 2026
Cover [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Mar. 31, 2026  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q1  
Entity Registrant Name TransMedics Group, Inc.  
Entity Central Index Key 0001756262  
Current Fiscal Year End Date --12-31  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Shell Company false  
Entity Emerging Growth Company false  
Entity Small Business false  
Entity Common Stock, Shares Outstanding   34,560,911
Entity File Number 001-38891  
Entity Incorporation, State or Country Code MA  
Entity Tax Identification Number 83-2181531  
Entity Address, Address Line One 200 Minuteman Road  
Entity Address, City or Town Andover  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 01810  
City Area Code 978  
Local Phone Number 552-0900  
Document Quarterly Report true  
Document Transition Report false  
Title of 12(b) Security Common Stock, No Par Value  
Trading Symbol TMDX  
Security Exchange Name NASDAQ