Document and Entity Information - shares
6 Months Ended
Jun. 30, 2019
Jul. 30, 2019
Entity Information [Line Items]    
Document Transition Report false  
Entity Incorporation, State or Country Code FL  
Title of 12(b) Security Common Stock, $0.10 Par Value  
Document Quarterly Report true  
Entity Tax Identification Number 59-0864469  
Entity Address, City or Town 220 South Ridgewood Avenue,  
Entity Address, Postal Zip Code 32114  
Entity Address, State or Province FL  
Entity Address, City or Town Daytona Beach,  
Security Exchange Name NYSE  
Entity Small Business false  
Entity Emerging Growth Company false  
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Jun. 30, 2019  
Entity File Number 001-13619  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q2  
Trading Symbol BRO  
Entity Registrant Name BROWN & BROWN, INC.  
City Area Code 386  
Local Phone Number 252-9601  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Central Index Key 0000079282  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   281,274,947