| Cover Page | Dec. 02, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Dec. 2, 2020 |
| Entity Registrant Name | Asbury Automotive Group, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-31262 |
| Entity Tax Identification Number | 01-0609375 |
| Entity Address, Address Line One | 2905 Premiere Parkway NW Suite 300 |
| Entity Address, City or Town | Duluth, |
| Entity Address, State or Province | GA |
| Entity Address, Postal Zip Code | 30097 |
| City Area Code | 770 |
| Local Phone Number | 418-8200 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common stock, $0.01 par value per share |
| Trading Symbol | ABG |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001144980 |
| Amendment Flag | false |
