Fair Value Measurements - Additional Information (Details) - USD ($) $ in Millions	Feb. 03, 2019	May 04, 2019
Fair Value Disclosures [Abstract]
Securities with maturity dates within one year or less		$ 34.3
Securities with maturity dates over one year and less than two years		$ 28.5
ASU 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment on retained earnings	$ 1.3

Amount of the cumulative effect on retained earnings net of related income tax effect.

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Amount of investment in marketable security, classified as current.

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