Revenue recognition - Performance Obligation Narrative (Details)	12 Months Ended
Jan. 31, 2026
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Performance Obligation Satisfied over Time, Method Used, Explanation	5
Extended Service Plans and Lifetime Warranty Agreements \| North America
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, performance obligation, description of timing	13 years
Extended Service Plans and Lifetime Warranty Agreements \| North America \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-31
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected timing of satisfaction, period	2 years
Extended Service Plans and Lifetime Warranty Agreements \| North America \| Minimum \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-31
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percentage of revenue recognized	60.00%
Extended Service Plans and Lifetime Warranty Agreements \| North America \| Maximum \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-31
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percentage of revenue recognized	70.00%

Description of timing for satisfying performance obligation in contract with customer. Includes, but is not limited to, as services are rendered, and upon shipment, delivery or completion of service.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

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Description of why method used to recognize revenue provides faithful depiction of transfer of good and service for performance obligation satisfied over time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-18

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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

Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

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- Definition

Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

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