Financial Instruments - Gross Unrealized Losses and Fair Values (Details) - USD ($) $ in Thousands	Aug. 01, 2021	Jan. 31, 2021
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	$ 84,018	$ 41,297
Unrealized Loss, Less than 12 Months	(62)	(34)
Fair Value, Greater than 12 months	0	0
Unrealized Loss, Greater than 12 months	0	0
Fair Value, Total	84,018	41,297
Unrealized Loss, Total	(62)	(34)
U.S. government treasury notes
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	33,652	8,301
Unrealized Loss, Less than 12 Months	(8)	(1)
Fair Value, Greater than 12 months	0	0
Unrealized Loss, Greater than 12 months	0	0
Fair Value, Total	33,652	8,301
Unrealized Loss, Total	(8)	(1)
Corporate debt securities
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	44,011	32,996
Unrealized Loss, Less than 12 Months	(48)	(33)
Fair Value, Greater than 12 months	0	0
Unrealized Loss, Greater than 12 months	0	0
Fair Value, Total	44,011	32,996
Unrealized Loss, Total	(48)	$ (33)
Asset-backed securities
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	3,917
Unrealized Loss, Less than 12 Months	(4)
Fair Value, Greater than 12 months	0
Unrealized Loss, Greater than 12 months	0
Fair Value, Total	3,917
Unrealized Loss, Total	(4)
Municipal bonds
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Fair Value, Less than 12 months	2,438
Unrealized Loss, Less than 12 Months	(2)
Fair Value, Greater than 12 months	0
Unrealized Loss, Greater than 12 months	0
Fair Value, Total	2,438
Unrealized Loss, Total	$ (2)

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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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