Investments - Summary Of Investments (Details) - USD ($) $ in Thousands	Oct. 27, 2019	Jan. 27, 2019
Investment [Line Items]
Market Value	$ 7,847	$ 3,105
Adjusted Cost	7,652	3,105
Gross Unrealized Gain	195	0
Convertible debt
Investment [Line Items]
Market Value	7,847	3,105
Adjusted Cost	7,652	3,105
Gross Unrealized Gain	$ 195	$ 0

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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-Publisher FASB
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