Summary of Significant Accounting Policies (Fair Value of Financial Instruments) (Details) - USD ($) $ in Thousands	Apr. 29, 2023	Jan. 28, 2023	Apr. 30, 2022
Significant Accounting Policies [Line Items]
Amortized Cost	$ 88,241	$ 66,845	$ 189,140
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	35	292	1,198
Fair Market Value	88,206	66,553	187,942
Fair Value, Inputs, Level 1
Significant Accounting Policies [Line Items]
Cash equivalents	322,000	313,200	50,700
Corporate bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost	88,241	66,845	159,145
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	35	292	1,134
Fair Market Value	$ 88,206	$ 66,553	158,011
Municipal bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost			29,995
Gross Unrealized Gains			0
Gross Unrealized Losses			64
Fair Market Value			29,931
Corporate bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost			10,182
Gross Unrealized Gains			0
Gross Unrealized Losses			205
Fair Market Value			9,977
Other Long-term Investments
Significant Accounting Policies [Line Items]
Amortized Cost			10,182
Gross Unrealized Gains			0
Gross Unrealized Losses			205
Fair Market Value			$ 9,977

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Significant Accounting Policies [Line Items]

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

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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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