Summary of Significant Accounting Policies (Fair Value of Financial Instruments) (Details) - USD ($) $ in Thousands	Jul. 30, 2022	Jan. 29, 2022	Jul. 31, 2021
Significant Accounting Policies [Line Items]
Amortized Cost	$ 117,315	$ 277,141	$ 286,929
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	1,107	330	55
Fair Market Value	116,208	276,811	286,874
Other Long-term Investments
Significant Accounting Policies [Line Items]
Amortized Cost		37,717	1,104
Gross Unrealized Gains		0	1
Gross Unrealized Losses		199	0
Fair Market Value		37,518	1,105
Fair Value, Inputs, Level 1
Significant Accounting Policies [Line Items]
Cash equivalents	115,000	41,300	73,900
Corporate bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost	110,692	236,069	234,909
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	1,104	286	49
Fair Market Value	109,588	235,783	234,860
Municipal bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost	6,623	41,072	52,020
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	3	44	6
Fair Market Value	$ 6,620	41,028	52,014
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
Municipal bonds \| Fair Value, Inputs, Level 2
Significant Accounting Policies [Line Items]
Amortized Cost			1,104
Gross Unrealized Gains			1
Gross Unrealized Losses			0
Fair Market Value			$ 1,105

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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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