Description of a specific restructuring plan and related activities including the facts and circumstances leading to the restructuring or decision to exit an activity, and the expected completion date. This concept and related items would be utilized for each plan if multiple exit plans have been implemented in the period.

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Amount expected to be recognized in earnings for the specified restructuring cost.

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RESTRUCTURING - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
RESTRUCTURING - Narrative (Details) - USD ($) $ in Millions	Jun. 28, 2025	Jun. 29, 2024	Jun. 28, 2025	Jun. 29, 2024
Restructuring Cost and Reserve [Line Items]
Program costs to date	$ 158		$ 158
Restructuring charges	$ 9	$ 8	15	$ 109
Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Activities, Description	1
Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Activities, Description	5
North America
Restructuring Cost and Reserve [Line Items]
Program costs to date	$ 66		66
Restructuring charges	1	9	1	40
Employee Related Costs [Member]
Restructuring Cost and Reserve [Line Items]
Program costs to date	52		52
Restructuring charges	4	0	7	37
Asset related costs [Member]
Restructuring Cost and Reserve [Line Items]
Program costs to date	27		27
Restructuring charges	4	4	4	8
Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges			4
North America Frozen Supply Chain Network Reconfiguration
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	70		70
North America Frozen Supply Chain Network Reconfiguration \| COGS
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1	$ 9	1	40
North America Frozen Supply Chain Network Reconfiguration \| Employee Related Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	10		10
North America Frozen Supply Chain Network Reconfiguration \| Asset related costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	50		50
North America Frozen Supply Chain Network Reconfiguration \| Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	10		10
European Cereal Supply Chain Network Reconfiguration
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	120		120
Restructuring charges	8		14	$ 69
European Cereal Supply Chain Network Reconfiguration \| Employee Related Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	50		50
European Cereal Supply Chain Network Reconfiguration \| Asset related costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	40		40
European Cereal Supply Chain Network Reconfiguration \| Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related cost, expected cost	$ 30		$ 30