Restructuring and Cost Reduction Activities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	$ 143	$ 263	$ 325
Program cost to date	1,520
Employee related cost
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	63	177	108
Program cost to date	597
Pension curtailment (gain) loss, net
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	(30)	(148)	1
Program cost to date	(167)
Asset related costs
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	16	77	46
Program cost to date	285
Asset impairment
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	14	0	50
Program cost to date	169
Other cost
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	80	157	120
Program cost to date	636
U.S. Snacks
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	28	309	76
Program cost to date	531
U.S. Morning Foods
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	50	18	23
Program cost to date	301
U.S. Specialty
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	4	2	8
Program cost to date	25
North America Other
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	25	16	38
Program cost to date	165
Europe
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	3	40	126
Program cost to date	333
Latin America
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	15	9	8
Program cost to date	42
Asia Pacific
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	11	11	7
Program cost to date	98
Corporate
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	7	$ (142)	$ 39
Program cost to date	$ 25