Revenue and contract costs - Narrative (Details) - USD ($)	3 Months Ended
Apr. 30, 2024	Apr. 30, 2023
Revenue from External Customer [Line Items]
Capitalized contract cost, amortization	$ 192,000	$ 340,000
Capitalized contract cost, impairment loss	$ 0	0
Minimum
Revenue from External Customer [Line Items]
Capitalized contract cost, amortization period	3 years
Maximum
Revenue from External Customer [Line Items]
Capitalized contract cost, amortization period	5 years
Subscription and Related Services
Revenue from External Customer [Line Items]
Lease income	$ 2,388,000	$ 2,662,000

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479483/340-40-50-3

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- Definition

Amortization period of cost capitalized in obtaining or fulfilling contract with customer, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-SubTopic 40
-Topic 340
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479483/340-40-50-2

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- Definition

Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

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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.

+ References

No definition available.

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- Definition

Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479773/842-30-50-5

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