Dollar Tree, Inc. Annual report pursuant to Section 13 and 15(d)

Employee Benefit Plans (Details) $ in Millions	12 Months Ended
Employee Benefit Plans (Details) $ in Millions	Jan. 28, 2023 USD ($) year hour	Jan. 29, 2022 USD ($)	Jan. 30, 2021 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Age over which all employees have 401K benefits available \| year	18
Employee service years required for available 401K benefits (in years)	1 year
Minimum hours in a 401K qualifying one year period (in hours) \| hour	1,000
Plan expenses	$ 31.7	$ 28.8	$ 26.4
Cost of sales
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan expenses	8.6	8.2	7.4
Selling, general and administrative expenses
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan expenses	$ 23.1	$ 20.6	$ 19.0