Fair Value Measurement - Securities Carried at Amortized Cost Plus Accrued Interest (Details) - USD ($) $ in Thousands	May 04, 2019	Feb. 02, 2019
Investment securities classified as held to maturity
Amortized Cost	$ 50,912	$ 59,233
Fair Market Value	50,899	59,184
Short-term Investments
Investment securities classified as held to maturity
Amortized Cost	43,135	50,350
Gross Unrealized Gains	10	4
Gross Unrealized Losses	(22)	(37)
Fair Market Value	43,123	50,317
Short-term Investments \| Obligations of the U.S. Treasury \| Fair Value, Inputs, Level 1
Investment securities classified as held to maturity
Amortized Cost	34,329	38,706
Gross Unrealized Gains	10	4
Gross Unrealized Losses	(22)	(37)
Fair Market Value	34,317	38,673
Short-term Investments \| Obligations of states and municipalities \| Fair Value, Inputs, Level 2
Investment securities classified as held to maturity
Amortized Cost		95
Fair Market Value		95
Short-term Investments \| Bank certificates of deposit \| Fair Value, Inputs, Level 2
Investment securities classified as held to maturity
Amortized Cost	8,806	11,549
Fair Market Value	8,806	11,549
Long Term Investments
Investment securities classified as held to maturity
Amortized Cost	7,777	8,883
Gross Unrealized Losses	(1)	(16)
Fair Market Value	7,776	8,867
Long Term Investments \| Obligations of the U.S. Treasury \| Fair Value, Inputs, Level 1
Investment securities classified as held to maturity
Amortized Cost	990	4,956
Gross Unrealized Losses	(1)	(16)
Fair Market Value	989	4,940
Long Term Investments \| Bank certificates of deposit \| Fair Value, Inputs, Level 2
Investment securities classified as held to maturity
Amortized Cost	6,787	3,927
Fair Market Value	$ 6,787	$ 3,927

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 45
-Paragraph 1
-Subparagraph (b)
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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 5
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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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