Financial Instruments - Gross Unrealized Losses and Fair Values (Details) - USD ($) $ in Thousands	May 02, 2021	Jan. 31, 2021
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	$ 101,706	$ 41,297
Unrealized Loss, Less than 12 Months	(191)	(34)
Fair Value, Greater than 12 months	0	0
Unrealized Loss, Greater than 12 months	0	0
Fair Value, Total	101,706	41,297
Unrealized Loss, Total	(191)	(34)
U.S. government treasury notes
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	20,412	8,301
Unrealized Loss, Less than 12 Months	(14)	(1)
Fair Value, Greater than 12 months	0	0
Unrealized Loss, Greater than 12 months	0	0
Fair Value, Total	20,412	8,301
Unrealized Loss, Total	(14)	(1)
Corporate debt securities
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	74,897	32,996
Unrealized Loss, Less than 12 Months	(164)	(33)
Fair Value, Greater than 12 months	0	0
Unrealized Loss, Greater than 12 months	0	0
Fair Value, Total	74,897	32,996
Unrealized Loss, Total	(164)	$ (33)
Foreign government bonds
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	1,238
Unrealized Loss, Less than 12 Months	(2)
Fair Value, Greater than 12 months	0
Unrealized Loss, Greater than 12 months	0
Fair Value, Total	1,238
Unrealized Loss, Total	(2)
Asset-backed securities
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	2,727
Unrealized Loss, Less than 12 Months	(3)
Fair Value, Greater than 12 months	0
Unrealized Loss, Greater than 12 months	0
Fair Value, Total	2,727
Unrealized Loss, Total	(3)
Municipal bonds
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	2,432
Unrealized Loss, Less than 12 Months	(8)
Fair Value, Greater than 12 months	0
Unrealized Loss, Greater than 12 months	0
Fair Value, Total	2,432
Unrealized Loss, Total	$ (8)

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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