| Cover Page | May 27, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | May 27, 2020 |
| Entity Registrant Name | DOLLAR TREE, INC. |
| Entity Incorporation, State or Country Code | VA |
| Entity File Number | 0-25464 |
| Entity Tax Identification Number | 26-2018846 |
| Entity Central Index Key | 0000935703 |
| Amendment Flag | false |
| Entity Address, Address Line One | 500 Volvo Parkway |
| Entity Address, City or Town | Chesapeake, |
| Entity Address, State or Province | VA |
| Entity Address, Postal Zip Code | 23320 |
| City Area Code | 757 |
| Local Phone Number | 321-5000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, par value $.01 per share |
| Trading Symbol | DLTR |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
