Consolidated Statement of Income (Unaudited) - USD ($) shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Oct. 01, 2022	Oct. 02, 2021	Oct. 01, 2022	Oct. 02, 2021
Income Statement [Abstract]
Net sales	$ 3,946	$ 3,622	$ 11,482	$ 10,761
Cost of goods sold	2,793	2,457	8,027	7,206
Selling, general and administrative expense	785	718	2,155	2,132
Operating profit	368	447	1,300	1,423
Interest expense	39	55	149	172
Other income (expense), net	54	0	188	155
Income before income taxes	383	392	1,339	1,406
Income tax expense (benefit)	74	92	283	345
Earnings (loss) from unconsolidated entities	3	5	6	0
Net income	312	305	1,062	1,061
Net income attributable to noncontrolling interests	2	(2)	4	6
Net income attributable to Kellogg Company	$ 310	$ 307	$ 1,058	$ 1,055
Per share amounts:
Basic earnings (in dollars per share)	$ 0.91	$ 0.90	$ 3.11	$ 3.09
Diluted earnings (in dollars per share)	$ 0.90	$ 0.89	$ 3.09	$ 3.07
Average shares outstanding:
Basic (in shares)	341,000	341,000	340,000	341,000
Diluted (in shares)	344,000	343,000	343,000	343,000
Actual shares outstanding at period end (in shares)	341,000	341,000	341,000	341,000