Summary of Significant Accounting Policies (Fair Value of Financial Instruments) (Details) - USD ($) $ in Thousands	Feb. 01, 2020	Feb. 02, 2019
Municipal Bonds [Member]
Significant Accounting Policies [Line Items]
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment	$ 59,229	$ 85,412
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	4	65
Debt Securities, Held-to-maturity, Fair Value	59,225	85,347
Municipal Bonds [Member] \| Fair Value, Inputs, Level 2 [Member]
Significant Accounting Policies [Line Items]
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment	604	2,284
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	2
Debt Securities, Held-to-maturity, Fair Value	604	2,282
Corporate Bond Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Significant Accounting Policies [Line Items]
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment	58,625	83,128
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	4	63
Debt Securities, Held-to-maturity, Fair Value	$ 58,621	$ 83,065

Significant Accounting Policies [Line Items]

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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).

+ References

No definition available.

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- Definition

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

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