Fair Value Measurements - Financial Assets Based on Priority of Inputs to Valuation Technique Instruments (Details) - USD ($) $ in Thousands	Jul. 30, 2016	Jan. 30, 2016
Level 1 | Cash equivalents | Money market securities
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Cash equivalents	$ 50,848	$ 42,626
Level 1 | Marketable securities | Commercial paper
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Marketable securities	0	0
Level 2 | Cash equivalents | Money market securities
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Cash equivalents	0	0
Level 2 | Marketable securities | Commercial paper
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Marketable securities	39,926	49,932
Level 3 | Cash equivalents | Money market securities
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Cash equivalents	0	0
Level 3 | Marketable securities | Commercial paper
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Marketable securities	$ 0	$ 0