SHAREHOLDERS' EQUITY Stock Repurchase (Details) (USD $) In Millions, unless otherwise specified	May 03, 2014
Shares repurchased [Abstract]
Value of remaining shares authorized to repurchase	$ 1,000.0

Dollar amount of outstanding common stock that is authorized for repurchase under the board authorized share repurchase program.

No definition available.

Name:	dltr_DollarAmountOfSharesCommonStockAuthorizedToRepurchase
Namespace Prefix:	dltr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant