| Document And Entity Information | Jan. 27, 2020 |
| Document And Entity Information [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Jan. 27, 2020 |
| Entity Registrant Name | BROWNÂ & BROWN, INC. |
| Entity Central Index Key | 0000079282 |
| Entity Emerging Growth Company | false |
| Entity File Number | 001-13619 |
| Entity Incorporation, State or Country Code | FL |
| Entity Tax Identification Number | 59-0864469 |
| Entity Address, Address Line One | 220 South Ridgewood Avenue |
| Entity Address, City or Town | Daytona Beach |
| Entity Address, State or Province | FL |
| Entity Address, Postal Zip Code | 32114 |
| City Area Code | 386 |
| Local Phone Number | 252-9601 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of each class | Common Stock, $0.10 Par Value |
| Trading Symbol | BRO |
| Security Exchange Name | NYSE |
