Convertible Senior Notes - Schedule of Net Carrying Amount of the Liability Component of the Notes (Details) - USD ($) $ in Thousands	Oct. 31, 2021	Jan. 31, 2021
2024 Notes
Debt Instrument [Line Items]
Principal	$ 1,863	$ 90,000
Unamortized debt discount	0	(15,459)
Unamortized debt issuance costs	(25)	(1,265)
Net carrying amount	1,838	73,276
2026 Notes
Debt Instrument [Line Items]
Principal	1,149,991	1,150,000
Unamortized debt discount	0	(249,907)
Unamortized debt issuance costs	(14,307)	(13,174)
Net carrying amount	$ 1,135,684	$ 886,919