Convertible Senior Notes, Net - Schedule of Interest Expense (Details) - Senior Notes - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2022	Oct. 31, 2021	Oct. 31, 2022	Oct. 31, 2021
2023 convertible senior notes
Debt Instrument [Line Items]
Contractual interest expense	$ 3	$ 9	$ 14	$ 43
Amortization of debt issuance costs	8	22	35	84
Amortization of debt discount		213		837
Total	11	244	49	964
2025 convertible senior notes
Debt Instrument [Line Items]
Contractual interest expense	332	332	994	994
Amortization of debt issuance costs	809	581	2,424	1,705
Amortization of debt discount		8,878		26,368
Total	1,141	9,791	3,418	29,067
2026 convertible senior notes
Debt Instrument [Line Items]
Contractual interest expense	1,078	1,078	3,234	3,234
Amortization of debt issuance costs	628	364	1,881	1,056
Amortization of debt discount		11,640		34,428
Total	$ 1,706	$ 13,082	$ 5,115	$ 38,718

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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