Summary of Significant Accounting Policies (Fair Value of Financial Instruments) (Details) - USD ($) $ in Thousands	May 02, 2020	Feb. 01, 2020	May 04, 2019
Significant Accounting Policies [Line Items]
Amortized Cost	$ 69,220	$ 59,229	$ 67,875
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	33	4	24
Fair Market Value	69,187	59,225	67,851
Fair Value, Inputs, Level 1
Significant Accounting Policies [Line Items]
Cash equivalents	54,000	200,100	188,000
Corporate bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost	69,220	58,625	65,451
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	33	4	23
Fair Market Value	$ 69,187	58,621	65,428
Municipal bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost		604	2,424
Gross Unrealized Gains		0	0
Gross Unrealized Losses		0	1
Fair Market Value		$ 604	$ 2,423

Cash Equivalents

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- Definition

Significant Accounting Policies [Line Items]

+ References

No definition available.

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

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- Definition

Amount, before other-than-temporary impairment (OTTI) accretion, of investment in debt securities 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
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