CONSOLIDATED STATEMENT OF INCOME (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 28, 2024	Sep. 30, 2023	Sep. 28, 2024	Sep. 30, 2023
Income Statement [Abstract]
Net sales	$ 3,233	$ 3,255	$ 9,625	$ 9,948
Cost of goods sold	2,057	2,145	6,257	6,760
Selling, general and administrative expense	720	696	2,026	2,011
Operating profit	456	414	1,342	1,177
Interest expense	75	75	241	218
Other income (expense), net	21	(62)	97	(17)
Income from continuing operations before income taxes	402	277	1,198	942
Income taxes	34	78	213	216
Earnings (loss) from unconsolidated entities	2	(1)	3	4
Net income from continuing operations	370	198	988	730
Net income attributable to noncontrolling interests	3	1	10	10
Income (loss) from discontinued operations, net of taxes	0	72	0	204
Net income attributable to Kellanova	$ 367	$ 269	$ 978	$ 924
Earnings per common share - basic
Earnings (loss) from continuing operations - per common share basic	$ 1.07	$ 0.58	$ 2.86	$ 2.11
Earnings (loss) from discontinued operations - per common share basic	0	0.21	0	0.59
Net earnings (loss) per common share - basic	1.07	0.79	2.86	2.70
Earnings per common share - diluted
Earnings (loss) from continuing operations - per common share diluted	1.05	0.57	2.83	2.09
Earnings (loss) from discontinued operations - per common share diluted	0	0.21	0	0.59
Net earnings (loss) per common share - diluted	$ 1.05	$ 0.78	$ 2.83	$ 2.68
Average shares outstanding:
Basic (in shares)	343	342	342	342
Diluted (in shares)	347	345	345	345
Actual shares outstanding at period end (in shares)	345	343	345	343