Reportable Segments Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 29, 2018		Dec. 30, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Net sales	$ 3,317	$ 3,469	$ 3,360	$ 3,401	$ 3,185	$ 3,246	$ 3,175	$ 3,248	$ 13,547		$ 12,854	$ 12,965
Operating profit									1,706		1,387	1,483
Depreciation and amortization									516	[1]	481	517
Interest expense									287		256	406
Income taxes									181		410	235
Property, Plant and Equipment, Additions									578		501	507
Assets	17,780				16,351				17,780		16,351
U.S. Snacks
Segment Reporting Information [Line Items]
Net sales									2,957		3,110	3,197
Operating profit									446		138	325
Depreciation and amortization									138		146	159
U.S. Morning Foods
Segment Reporting Information [Line Items]
Net sales									2,643		2,709	2,917
Operating profit									478		567	597
Depreciation and amortization									127		120	122
U.S. Specialty
Segment Reporting Information [Line Items]
Net sales									1,235		1,242	1,207
Operating profit									251		312	279
Depreciation and amortization									12		13	11
North America Other
Segment Reporting Information [Line Items]
Net sales									1,853		1,612	1,593
Operating profit									222		229	181
Depreciation and amortization									64	[1]	51	56
Interest expense									1		3	5
North America [Member]
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Additions									336		329	318
Assets	10,777				10,867				10,777		10,867
Europe
Segment Reporting Information [Line Items]
Net sales									2,395		2,291	2,383
Operating profit									297		276	208
Depreciation and amortization									80		80	114
Interest expense									10		16	8
Income taxes									22		(39)	(16)
Property, Plant and Equipment, Additions									90		106	125
Assets	4,870				4,057				4,870		4,057
Latin America
Segment Reporting Information [Line Items]
Net sales									947		944	772
Operating profit									102		108	84
Depreciation and amortization									37		37	22
Interest expense									3		2	4
Income taxes									30		33	30
Property, Plant and Equipment, Additions									76		32	24
Assets	1,060				1,094				1,060		1,094
Asia Pacific
Segment Reporting Information [Line Items]
Net sales									1,517		946	896
Operating profit									128		84	69
Depreciation and amortization									55		33	30
Interest expense									5		2	2
Income taxes									24		12	14
Property, Plant and Equipment, Additions									73		30	36
Assets	2,812				1,226				2,812		1,226
Total Reportable Segments [Member]
Segment Reporting Information [Line Items]
Operating profit									1,924		1,714	1,743
Depreciation and amortization									513	[1]	480	514
Corporate
Segment Reporting Information [Line Items]
Operating profit									(218)		(327)	(260)
Depreciation and amortization									3		1	3
Interest expense									268		233	387
Property, Plant and Equipment, Additions									3		4	4
Assets	649				1,426				649		1,426
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Assets	$ (2,388)				$ (2,319)				(2,388)		(2,319)
Corporate And North America [Member]
Segment Reporting Information [Line Items]
Income taxes									$ 105		$ 404	$ 207

[1] Includes asset impairment charges as discussed in Note 14.