Summary of Significant Accounting Policies (Fair Value of Financial Instruments) (Details) - USD ($) $ in Thousands	Oct. 29, 2022	Jan. 29, 2022	Oct. 30, 2021
Significant Accounting Policies [Line Items]
Amortized Cost	$ 72,722	$ 277,141	$ 224,563
Gross Unrealized Gains	0	0	6
Gross Unrealized Losses	813	330	93
Fair Market Value	71,909	276,811	224,476
Fair Value, Inputs, Level 1
Significant Accounting Policies [Line Items]
Cash equivalents	21,700	41,300	60,800
Corporate bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost	72,522	236,069	190,700
Gross Unrealized Gains	0	0	6
Gross Unrealized Losses	813	286	82
Fair Market Value	71,709	235,783	190,624
Municipal bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost	200	41,072	33,863
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	0	44	11
Fair Market Value	$ 200	41,028	$ 33,852
Corporate bonds
Significant Accounting Policies [Line Items]
Amortized Cost		37,717
Gross Unrealized Gains		0
Gross Unrealized Losses		199
Fair Market Value		37,518
Corporate bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost		37,717
Gross Unrealized Gains		0
Gross Unrealized Losses		199
Fair Market Value		$ 37,518

Cash Equivalents

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Significant Accounting Policies [Line Items]

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- Definition

Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

+ References

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

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