v3.23.1

Background and liquidity (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2023	Mar. 10, 2023	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Debt Instrument [Line Items]
Cash and cash equivalents	$ 176,683		$ 313,812	$ 218,781	$ 90,315
Third SVB Facility
Debt Instrument [Line Items]
Number of months with sufficient funds to operate (in months)	12 months
Third SVB Facility | Subsequent event
Debt Instrument [Line Items]
Cash and cash equivalents		$ 170,000
Third SVB Facility | Revolving credit facility | Subsequent event
Debt Instrument [Line Items]
Allowable cash hold outside of facility		$ 165,000

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- Definition

Debt Instrument, Covenant, Cash Hold Outside Of Facility

+ References

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- Definition

Estimated Number Of Months The Company Have Sufficient To Fund Its Operations

+ References

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- Definition

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3521-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3044-108585

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 8
-URI https://asc.fasb.org/extlink&oid=126999549&loc=SL98516268-108586

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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