Short-Term Investment Reconciliation - (Details) - USD ($) $ in Thousands	12 Months Ended
Feb. 02, 2019	Feb. 03, 2018
Debt Securiteis Issued by Various States of the United States and Political Subdivisions of the States
ScheduleOfAvailableForSaleSecuritiesLineItems
Cost Basis	$ 71,953	$ 96,701
Estimated Fair Value	71,582	95,983
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(371)	(718)
Corporate Debt Securities
ScheduleOfAvailableForSaleSecuritiesLineItems
Cost Basis	114,372	23,079
Estimated Fair Value	114,225	22,853
Gross Unrealized Gains	0	0
Gross Unrealized Losses	$ (147)	$ (226)

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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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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