Revenue recognition - ESP Deferred Revenue Rollforward (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Nov. 01, 2025	Nov. 02, 2024	Nov. 01, 2025	Nov. 02, 2024
Change in Contract with Customer, Liability [Roll Forward]
ESP deferred revenue, beginning of period			$ 1,247.6
Plans sold			(20.0)	$ (41.8)
ESP deferred revenue, end of period	$ 1,228.8	$ 1,202.0	1,228.8	1,202.0
ESP deferred revenue
Change in Contract with Customer, Liability [Roll Forward]
ESP deferred revenue, beginning of period	1,170.5	1,146.1	1,170.8	1,158.7
Plans sold	119.7	106.7	387.1	345.6
Revenue recognized	(129.6)	(120.1)	(397.3)	(371.6)
ESP deferred revenue, end of period	1,160.6	1,132.7	1,160.6	1,132.7
Extended Service Plan and other deferred revenue
Change in Contract with Customer, Liability [Roll Forward]
Revenue recognized	$ (69.9)	$ (67.6)	$ (235.0)	$ (227.8)

Change in Contract with Customer, Liability [Roll Forward]

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-URI https://asc.fasb.org/1943274/2147479837/606-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Section 45
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-URI https://asc.fasb.org/1943274/2147479837/606-10-45-2

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

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- Definition

Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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