Operating leases - Supplemental Operating Leases Information Table (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 29, 2024	Jul. 01, 2023	Jun. 29, 2024	Jul. 01, 2023
Lessee, Lease, Description [Line Items]
Operating cash flows from operating leases	$ 3	$ 0	$ 5	$ 0
New leases
Right-of-use assets obtained in exchange for operating lease liabilities
Right-of-use assets obtained in exchange for operating lease liabilities	16	0	52	0
Modified leases
Right-of-use assets obtained in exchange for operating lease liabilities
Right-of-use assets obtained in exchange for operating lease liabilities	$ 0	$ 0	$ 0	$ 0

Right-Of-Use Assets Obtained In Exchange For Operating Lease Liabilities

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (c)
-Publisher FASB
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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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-Section 50
-Paragraph 4
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-4

+ Details

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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 53
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479589/842-20-55-53

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-SubTopic 20
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-Paragraph 4
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-URI https://asc.fasb.org/1943274/2147478964/842-20-50-4

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