v3.25.2
Document and Entity Information - shares
6 Months Ended
Jun. 30, 2025
Jul. 29, 2025
Cover [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Jun. 30, 2025  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q2  
Trading Symbol BEAM  
Entity Registrant Name Beam Therapeutics Inc.  
Entity Central Index Key 0001745999  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Entity Emerging Growth Company false  
Entity Small Business false  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Shell Company false  
Title of 12(b) Security Common Stock, par value $0.01 per share  
Security Exchange Name NASDAQ  
Entity File Number 001-39208  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 81-5238376  
Entity Address, Address Line One 238 Main Street  
Entity Address, City or Town Cambridge  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 02142  
City Area Code 857  
Local Phone Number 327-8775  
Document Quarterly Report true  
Document Transition Report false  
Entity Common Stock, Shares Outstanding   101,162,026