Convertible Senior Notes - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2022	Oct. 31, 2021	Oct. 31, 2022	Oct. 31, 2021
Debt Instrument
Amortization of debt issuance costs			$ 7,878	$ 98,958
Convertible Senior Notes | 2023 Notes
Debt Instrument
Coupon interest expense	$ 971	$ 971	2,913	2,913
Amortization of debt discount (conversion option) (1)	0	8,497	0	24,832
Amortization of debt issuance costs	422	331	1,388	968
Total interest expense	1,393	9,799	4,301	28,713
Convertible Senior Notes | 2025 Notes
Debt Instrument
Coupon interest expense	2,426	2,426	7,278	7,278
Amortization of debt discount (conversion option) (1)	0	8,253	0	24,037
Amortization of debt issuance costs	345	227	1,211	662
Total interest expense	2,771	10,906	8,489	31,977
Convertible Senior Notes | 2026 Notes
Debt Instrument
Coupon interest expense	1,875	1,875	5,625	2,333
Amortization of debt discount (conversion option) (1)	0	12,107	0	15,067
Amortization of debt issuance costs	911	510	2,855	643
Total interest expense	2,786	14,492	8,480	18,043
Convertible Senior Notes | 2027 Notes
Debt Instrument
Coupon interest expense	3,558	3,558	10,674	10,674
Amortization of debt discount (conversion option) (1)	0	10,809	0	31,468
Amortization of debt issuance costs	716	440	2,424	1,281
Total interest expense	$ 4,274	$ 14,807	$ 13,098	$ 43,423