Supplemental financial statement information - Schedule of Other Income, Net (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2026	Apr. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interest income	$ 1,887	$ 2,733
Other miscellaneous income, net	161	0
Total other income, net	$ 2,048	$ 2,733

Amount of income (expense) related to nonoperating activities, classified as other.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(9))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration