Investments - Available-for-Sale Marketable Securities, Fair Value and Unrealized Losses Continuous Unrealized Loss Position (Details) $ in Thousands	Jan. 31, 2022 USD ($)
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
AFS, Less Than 12 Months, Unrealized Losses	$ (490)
AFS, Less Than 12 Months, Fair Value	181,508
AFS, 12 Months or Greater, Unrealized Losses	(313)
AFS, 12 Months or Greater, Fair Value	52,312
AFS, Total Unrealized Losses	(803)
AFS, Total Fair Value	233,820
Certificates of deposit
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
AFS, Less Than 12 Months, Unrealized Losses	0
AFS, Less Than 12 Months, Fair Value	12,500
AFS, 12 Months or Greater, Unrealized Losses	0
AFS, 12 Months or Greater, Fair Value	0
AFS, Total Unrealized Losses	0
AFS, Total Fair Value	12,500
U.S. government agencies securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
AFS, Less Than 12 Months, Unrealized Losses	0
AFS, Less Than 12 Months, Fair Value	0
AFS, 12 Months or Greater, Unrealized Losses	(105)
AFS, 12 Months or Greater, Fair Value	14,015
AFS, Total Unrealized Losses	(105)
AFS, Total Fair Value	14,015
Commercial paper
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
AFS, Less Than 12 Months, Unrealized Losses	0
AFS, Less Than 12 Months, Fair Value	14,493
AFS, 12 Months or Greater, Unrealized Losses	0
AFS, 12 Months or Greater, Fair Value	0
AFS, Total Unrealized Losses	0
AFS, Total Fair Value	14,493
Corporate debt securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
AFS, Less Than 12 Months, Unrealized Losses	(490)
AFS, Less Than 12 Months, Fair Value	154,515
AFS, 12 Months or Greater, Unrealized Losses	(208)
AFS, 12 Months or Greater, Fair Value	38,297
AFS, Total Unrealized Losses	(698)
AFS, Total Fair Value	$ 192,812

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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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