DIVESTITURES (Notes)	9 Months Ended
Sep. 27, 2025
Discontinued Operations and Disposal Groups [Abstract]
Divestiture	DIVESTITURES Egypt In September 2024, the Company entered into an agreement to sell a foreign subsidiary in Egypt. In conjunction with the agreement, the Company reclassified related assets and liabilities to held-for-sale and recognized an immaterial impairment charge in the AMEA reportable segment in OIE. Additionally, in 2024 the Company recognized a domestic tax benefit of $41 million for the excess of tax basis over book on the Company's investment in the subsidiary. The sale of the subsidiary was completed in the second quarter of 2025. The business in Egypt represented less than 1% of consolidated Kellanova net sales.

The entire disclosure for business combinations, including leverage buyout transactions (as applicable), and divestitures. This may include a description of a business combination or divestiture (or series of individually immaterial business combinations or divestitures) completed during the period, including background, timing, and assets and liabilities recognized and reclassified or sold. This element does not include fixed asset sales and plant closings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/805/tableOfContent

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