DISCONTINUED OPERATIONS - Schedule of Key Components of Income from Discontinued Operations (Details) - WK Kellogg Co - Discontinued Operations - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales - discontinued operations	$ 684	$ 2,085
Costs of goods sold - discontinued operations	451	1,387
Selling, general and administrative expense - discontinued operations	165	444
Operating profit - discontinued operations	68	254
Interest expense - discontinued operations	8	27
Other income (expense), net - discontinued operations	38	55
Income from discontinued operations before income taxes	98	282
Income taxes - discontinued operations	26	78
Net income from discontinued operations, net of tax	$ 72	$ 204