Fair Value Measurement - Amortized Cost and Fair Market Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Feb. 01, 2020	Feb. 02, 2019
Amortized Cost
Mature in one year or less	$ 27,562	$ 50,350
Mature after one year through five years	15,675	8,883
Total	43,237	59,233
Fair Market Value
Mature in one year or less	27,568	50,317
Mature after one year through five years	15,674	8,867
Fair Market Value	$ 43,242	$ 59,184

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

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