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Spin-off (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Spin-off (Details) - USD ($) $ in Millions	Jul. 03, 2026	Jul. 04, 2025	Jul. 03, 2026	Jul. 04, 2025
Restructuring Cost and Reserve [Line Items]
Restructuring charges and asset impairments	$ 31	$ 0	$ 46	$ 0
Other charges associated with lease right-of-use asset impairment			17	$ 0
MTS
Restructuring Cost and Reserve [Line Items]
Restructuring charges and asset impairments	15		16
Corporate
Restructuring Cost and Reserve [Line Items]
Restructuring charges and asset impairments	15		28
Spin-off
Restructuring Cost and Reserve [Line Items]
Restructuring charges and asset impairments	31
Other charges associated with lease right-of-use asset impairment	16		16
Leasehold impairment charges	1		1
Spin-off \| MTS
Restructuring Cost and Reserve [Line Items]
Impairment charges	13		13
Spin-off \| Corporate
Restructuring Cost and Reserve [Line Items]
Impairment charges	$ 4		$ 4