| Segments - Narrative (Details) | 3 Months Ended | 
|---|---|
| May 02, 2020  USD ($)  state  store  province  distribution_center  segment | |
| Segment Reporting Information [Line Items] | |
| Number of retail discount stores | store | 15,300 | 
| Number of states/provinces the Company operates in | state | 48 | 
| Number of reporting business segments | segment | 2 | 
| Dollar Tree | |
| Segment Reporting Information [Line Items] | |
| Merchandise fixed price | $ | $ 1.00 | 
| Family Dollar | |
| Segment Reporting Information [Line Items] | |
| Number of distribution centers | 11 | 
| Canada | |
| Segment Reporting Information [Line Items] | |
| Number of states/provinces the Company operates in | province | 5 | 
| Canada | Dollar Tree | |
| Segment Reporting Information [Line Items] | |
| Number of distribution centers | 2 | 
| United States | Dollar Tree | |
| Segment Reporting Information [Line Items] | |
| Number of distribution centers | 13 | 
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- Definition Fixed price for offering merchandise in discount variety stores No definition available. 
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- Definition Number Of Distribution Centers No definition available. 
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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. No definition available. 
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- Definition The number of states the entity operates in as of the balance sheet date. No definition available. 
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- Definition Represents the number of stores. No definition available. 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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