Fair Value Measurements (Details)
3 Months Ended 9 Months Ended
Nov. 03, 2018
USD ($)
Oct. 28, 2017
USD ($)
Apr. 29, 2017
USD ($)
store
Nov. 03, 2018
USD ($)
Oct. 28, 2017
USD ($)
Feb. 03, 2018
USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Impairment charge $ 0 $ 0 $ 5,500,000 $ 0 $ 5,479,000  
Number of stores impaired during the period | store     17      
Recurring [Member] | Level 1 [Member]            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Financial assets           $ 139,920,000
Recurring [Member] | Level 1 [Member] | Money market funds [Member]            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Financial assets 134,183,000     134,183,000   139,920,000
Recurring [Member] | Level 1 [Member] | Commercial paper [Member]            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Financial assets           0
Recurring [Member] | Level 2 [Member]            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Financial assets           79,908,000
Recurring [Member] | Level 2 [Member] | Money market funds [Member]            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Financial assets 0     0   0
Recurring [Member] | Level 2 [Member] | Commercial paper [Member]            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Financial assets           79,908,000
Recurring [Member] | Level 3 [Member]            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Financial assets           0
Recurring [Member] | Level 3 [Member] | Money market funds [Member]            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Financial assets $ 0     $ 0   0
Recurring [Member] | Level 3 [Member] | Commercial paper [Member]            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Financial assets           $ 0