v3.25.1
Document And Entity Information - shares
3 Months Ended
Mar. 31, 2025
Apr. 23, 2025
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2025  
Document Transition Report false  
Entity File Number 001-15811  
Entity Registrant Name MARKEL GROUP INC.  
Entity Incorporation, State or Country Code VA  
Entity Tax Identification Number 54-1959284  
Entity Address, Address Line One 4521 Highwoods Parkway  
Entity Address, City or Town Glen Allen  
Entity Address, State or Province VA  
Entity Address, Postal Zip Code 23060-6148  
City Area Code 804  
Local Phone Number 747-0136  
Title of 12(b) Security Common Stock, no par value  
Trading Symbol MKL  
Security Exchange Name NYSE  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   12,684,687
Amendment Flag false  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q1  
Entity Central Index Key 0001096343  
Current Fiscal Year End Date --12-31