Summary of Significant Accounting Policies (Fair Value of Financial Instruments) (Details) - USD ($) $ in Thousands	Jan. 29, 2022	Jan. 30, 2021
Municipal Bonds [Member]
Significant Accounting Policies [Line Items]
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment	$ 277,141	$ 140,928
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	330	60
Debt Securities, Held-to-maturity, Fair Value	276,811	140,868
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	41,072	45,398
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	44	7
Debt Securities, Held-to-maturity, Fair Value	41,028	45,391
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	236,069	95,530
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	286	53
Debt Securities, Held-to-maturity, Fair Value	235,783	$ 95,477
Other Long-term Investments
Significant Accounting Policies [Line Items]
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment	37,717
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	199
Debt Securities, Held-to-maturity, Fair Value	37,518
Other Long-term Investments \| Fair Value, Inputs, Level 2 [Member]
Significant Accounting Policies [Line Items]
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment	37,717
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	199
Debt Securities, Held-to-maturity, Fair Value	$ 37,518

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).

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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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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).

+ 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=123581744&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=SL120269820-111563

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