Consolidated Statement of Income Statement - USD ($) $ in Millions	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Income Statement [Abstract]
Net sales	$ 13,547	$ 12,854	$ 12,965
Cost of goods sold	8,821	8,155	8,131
Selling, general and administrative expense	3,020	3,312	3,351
Operating profit	1,706	1,387	1,483
Interest expense	287	256	406
Other income (expense), net	(90)	526	(143)
Income before income taxes	1,329	1,657	934
Income taxes	181	410	235
Earnings (loss) from unconsolidated entities	196	7	1
Net income	1,344	1,254	700
Net income (loss) attributable to noncontrolling interests	8	0	1
Net income attributable to Kellogg Company	$ 1,336	$ 1,254	$ 699
Basic	$ 3.85	$ 3.61	$ 1.99
Diluted	$ 3.83	$ 3.58	$ 1.97