REPORTABLE SEGMENTS - Supplemental Product Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 29, 2025	Mar. 30, 2024
Segment Reporting Information [Line Items]
Net sales	$ 3,083	$ 3,200
Snacks
Segment Reporting Information [Line Items]
Net sales	1,897	2,015
Cereal
Segment Reporting Information [Line Items]
Net sales	645	687
Frozen
Segment Reporting Information [Line Items]
Net sales	290	290
Noodles and other
Segment Reporting Information [Line Items]
Net sales	$ 251	$ 208