Fair Value Measurements - Financial Assets Based on Priority of Inputs to Valuation Technique Instruments (Details) - USD ($) $ in Thousands	May 02, 2020	Feb. 01, 2020	May 04, 2019
Money market securities | Level 1 | Cash equivalents
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Cash equivalents	$ 62,906	$ 58,614	$ 27,494
Money market securities | Level 2 | Cash equivalents
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Cash equivalents	0	0	0
Money market securities | Level 3 | Cash equivalents
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Cash equivalents	0	0	0
Commercial paper | Level 1 | Cash equivalents
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Cash equivalents	0	0	0
Commercial paper | Level 1 | Marketable securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable securities	0	0	0
Commercial paper | Level 2 | Cash equivalents
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Cash equivalents	0	0	0
Commercial paper | Level 2 | Marketable securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable securities	34,973	54,756	49,576
Commercial paper | Level 3 | Cash equivalents
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Cash equivalents	0	0	0
Commercial paper | Level 3 | Marketable securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable securities	$ 0	$ 0	$ 0