Equity method investments - Unaudited financial information (Detail) - USD ($) $ in Millions	3 Months Ended				6 Months Ended		9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 24, 2022	Dec. 31, 2021	Dec. 25, 2021
Schedule Of Equity Method Investments [Line Items]
Assets	$ 902,296						$ 902,296			$ 958,784
Sales/ Total revenues and other income	76,934		$ 70,583				223,924	$ 204,296
The Kraft Heinz Company [Member]
Schedule Of Equity Method Investments [Line Items]
Assets									$ 89,992		$ 93,394
Liabilities									$ 41,649		$ 43,942
Sales/ Total revenues and other income	6,505		6,324				19,104	19,333
Net earnings (loss) attributable to common shareholders	$ 432		$ 733				$ 1,473	$ 1,269
Occidental Petroleum Corporation [Member]
Schedule Of Equity Method Investments [Line Items]
Assets		$ 74,221			$ 74,221					75,036
Liabilities		46,391			46,391					$ 54,709
Sales/ Total revenues and other income		10,735		$ 6,010	19,268	$ 11,489
Net earnings (loss) attributable to common shareholders		$ 3,555		$ (97)	$ 8,231	$ (443)