Fair Value Measurement - Securities Carried at Amortized Cost Plus Accrued Interest (Details) - USD ($) $ in Thousands	3 Months Ended
May 02, 2020	Feb. 01, 2020
Investment securities classified as held to maturity
Amortized Cost		$ 43,237
Fair Market Value		43,242
Short-term Investments
Investment securities classified as held to maturity
Amortized Cost	$ 5	27,562
Gross Unrealized Gains		8
Gross Unrealized Losses		(2)
Fair Market Value	5	27,568
Net gains from the sales of investment securities	38,300
Short-term Investments \| Obligations of the U.S. Treasury and U.S. government agencies \| Fair Value, Inputs, Level 1
Investment securities classified as held to maturity
Amortized Cost	5	17,277
Gross Unrealized Gains		8
Gross Unrealized Losses		(2)
Fair Market Value	5	17,283
Short-term Investments \| Bank certificates of deposit \| Fair Value, Inputs, Level 2
Investment securities classified as held to maturity
Amortized Cost		10,285
Fair Market Value		10,285
Long Term Investments
Investment securities classified as held to maturity
Amortized Cost		15,675
Gross Unrealized Losses		(1)
Fair Market Value		15,674
Net gains from the sales of investment securities	$ 12,500
Long Term Investments \| Obligations of the U.S. Treasury and U.S. government agencies \| Fair Value, Inputs, Level 1
Investment securities classified as held to maturity
Amortized Cost		1,908
Gross Unrealized Losses		(1)
Fair Market Value		1,907
Long Term Investments \| Bank certificates of deposit \| Fair Value, Inputs, Level 2
Investment securities classified as held to maturity
Amortized Cost		13,767
Fair Market Value		$ 13,767

The difference between the carrying value and the sale price of an investment. A gain would be recognized when the sale price of the investment is greater than the carrying value of the investment. This element refers to the Gain included in earnings and not to the cash proceeds of the sale.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3)(a))
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13))
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-03(b)(9)(a))
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Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
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-Subparagraph (SX 210.5-03(b)(7)(c))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-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

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

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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