Fair Value Measurements (Schedule of Financial Instruments Measure at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands	May 01, 2021	Jan. 30, 2021	May 02, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents - money market mutual funds	$ 175,612	$ 97,519	$ 3,128
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents - money market mutual funds	175,612	97,519	3,128
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents - money market mutual funds	0	0	0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents - money market mutual funds	$ 0	$ 0	$ 0