XML 12 R1.htm IDEA: XBRL DOCUMENT v3.25.3
Cover - shares
 9 Months Ended
Sep. 30, 2025
Oct. 31, 2025
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Sep. 30, 2025  
Document Transition Report false  
Entity File Number 001-15781  
Entity Registrant Name BEACON FINANCIAL CORPORATION  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 04-3510455  
Entity Address, Address Line One 131 Clarendon Street  
Entity Address, City or Town Boston  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 02116  
City Area Code 617  
Local Phone Number 425-4600  
Title of 12(b) Security Common Stock  
Trading Symbol BBT  
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 false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   83,908,861
Entity Central Index Key 0001108134  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q3  
Amendment Flag false