Equity method investments - Unaudited financial information (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 26, 2020	Dec. 31, 2019	Dec. 28, 2019
Schedule of Equity Method Investments [Line Items]
Assets		$ 829,946		$ 829,946			$ 817,729
Liabilities		410,731		410,731			$ 389,166
Sales		63,024	$ 64,972	181,129	$ 189,248
The Kraft Heinz Company [Member]
Schedule of Equity Method Investments [Line Items]
Assets						$ 98,122		$ 101,450
Liabilities						$ 48,783		$ 49,701
Sales		6,441	6,076	19,246	18,441
Net earnings (loss) attributable to Kraft Heinz common shareholders*	[1]	$ 597	$ 899	$ (676)	$ 1,753

[1] Includes goodwill and identifiable intangible asset impairment charges of approximately $3.2 billion in the first nine months of 2020 and $1.1 billion in the first nine months of 2019.