Investments - Summary of Maturities of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Oct. 27, 2019	Jan. 27, 2019
Market Value
Within 1 year	$ 2,027	$ 3,105
After 1 year through 5 years	5,820	0
Total available-for-sale securities	7,847	3,105
Adjusted Cost
Within 1 year	1,993	3,105
After 1 year through 5 years	5,659	0
Total available-for-sale securities	$ 7,652	$ 3,105

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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