Available-for-sale securities - Summary of Maturities of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Aug. 01, 2021	Jan. 31, 2021
Fair Value
Within 1 year	$ 11,299
After 1 year through 5 years	356
Total available-for-sale securities	11,655	$ 11,989
Amortized Cost
Within 1 year	12,593
After 1 year through 5 years	843
Total available-for-sale securities	$ 13,436	$ 13,244

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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