Fair Value Measurement - Amortized Cost and Fair Market Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Aug. 03, 2019	Feb. 02, 2019
Amortized Cost
Mature in one year or less	$ 37,776	$ 50,350
Mature after one year through five years	16,976	8,883
Total	54,752	59,233
Fair Market Value
Mature in one year or less	37,794	50,317
Mature after one year through five years	16,982	8,867
Fair Market Value	54,776	$ 59,184
Changes among the fair value levels
Changes between Level 1 to Level 2, Assets	$ 0

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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