| Other intangible assets - Subject to amortization (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
|---|---|---|---|
| Feb. 01, 2025 | Feb. 03, 2024 | Jan. 28, 2023 | |
| Other intangible assets | |||
| Net | $ 204 | ||
| Amortization expense related to intangible assets | $ 306 | $ 889 | $ 1,014 | 
| Developed technology | |||
| Other intangible assets | |||
| Weighted-average remaining useful life | 8 months 12 days | ||
| Gross carrying value | $ 5,506 | 5,506 | |
| Accumulated amortization | (5,302) | (4,996) | |
| Net | $ 204 | $ 510 | |
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/exampleRef 
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/exampleRef 
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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. Reference 1: http://www.xbrl.org/2003/role/exampleRef 
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Details 
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