Fair Value Measurement - Amortized Cost and Fair Market Value of Securities by Contractual Maturity (Details) $ in Thousands	Feb. 01, 2020 USD ($)
Amortized Cost
Mature in one year or less	$ 27,562
Mature after one year through five years	15,675
Total	43,237
Fair Market Value
Mature in one year or less	27,568
Mature after one year through five years	15,674
Fair Market Value	$ 43,242

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

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