Quarterly report pursuant to Section 13 or 15(d)

Document And Entity Information

Document And Entity Information - shares
9 Months Ended
Nov. 03, 2018
Nov. 26, 2018
Document and Entity Information [Text Block] [Abstract]    
Entity Registrant Name Dollar Tree Inc  
Entity Central Index Key 0000935703  
Current Fiscal Year End Date --02-02  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   237,969,961
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q3  
Document Type 10-Q  
Amendment Flag false  
Entity Emerging Growth Company false  
Entity Small Business false  
Document Period End Date Nov. 03, 2018