Reportable Segments (Details) $ in Millions		3 Months Ended		9 Months Ended
	Jul. 28, 2019 USD ($)	Sep. 26, 2020 USD ($)	Sep. 28, 2019 USD ($)	Sep. 26, 2020 USD ($)	Sep. 28, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments				4
Net sales		$ 3,429	$ 3,372	$ 10,306	$ 10,355
Operating profit		411	263	1,376	1,041
Cash proceeds from sale of businesses				0	1,332
Operating Segments
Segment Reporting Information [Line Items]
Operating profit		473	352	1,601	1,280
Operating Segments | North America
Segment Reporting Information [Line Items]
Net sales		2,059	2,059	6,323	6,496
Operating profit		321	208	1,151	910
Operating Segments | Europe
Segment Reporting Information [Line Items]
Net sales		552	527	1,624	1,566
Operating profit		63	68	224	164
Operating Segments | Latin America
Segment Reporting Information [Line Items]
Net sales		236	244	686	707
Operating profit		31	23	84	61
Operating Segments | AMEA
Segment Reporting Information [Line Items]
Net sales		582	542	1,673	1,586
Operating profit		58	53	142	145
Corporate
Segment Reporting Information [Line Items]
Operating profit		$ (62)	(89)	$ (225)	(239)
Cookies, fruit and fruit-flavored snacks, pie crusts and ice cream cones businesses
Segment Reporting Information [Line Items]
Cash proceeds from sale of businesses	$ 1,300
Net assets	$ 1,300
Cookies, fruit and fruit-flavored snacks, pie crusts and ice cream cones businesses | North America
Segment Reporting Information [Line Items]
Net sales			$ 55		$ 562