DESCRIPTION OF THE COMPANY AND BASIS OF PRESENTATION - Allocation of Expenses from Kellanova (Details) $ in Millions	12 Months Ended
Dec. 28, 2024 USD ($) segment	Dec. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Related Party Transaction [Line Items]
Cost of goods sold	$ 1,915	$ 2,009	$ 2,064
Selling, general and administrative expense	631	662	556
Other income (expense), net	$ (6)	(63)	101
Number of reportable segments \| segment	1
Kellanova
Related Party Transaction [Line Items]
Cost of goods sold		128	172
Selling, general and administrative expense		233	308
Other income (expense), net		(43)	106
Total		$ 318	$ 586

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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