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

Employee Benefit Plans (Details)

Employee Benefit Plans (Details) $ in Millions	12 Months Ended
Employee Benefit Plans (Details) $ in Millions	Feb. 01, 2020 USD ($) hour year	Feb. 02, 2019 USD ($)	Feb. 03, 2018 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Age over which all employees have 401K benefits available \| year	21
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	$ 25.1	$ 41.4	$ 52.9
Cost of sales
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan expenses	8.1	8.7	7.8
Selling, general and administrative expenses
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plan expenses	$ 17.0	$ 32.7	$ 45.1
Profit Sharing Plan \| Tranche one
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Vesting percentage	20.00%
Service years	2 years
Profit Sharing Plan \| Tranche two
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Vesting percentage	40.00%
Service years	3 years
Profit Sharing Plan \| Tranche three
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Vesting percentage	60.00%
Service years	4 years
Profit Sharing Plan \| Tranche four
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Vesting percentage	100.00%
Service years	5 years