Equity method investments - Unaudited financial information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023	Mar. 29, 2025	Dec. 28, 2024	Sep. 30, 2024
Schedule Of Equity Method Investments [Line Items]
Assets	$ 1,164,532	$ 1,153,881
Liabilities	507,790	502,226
Sales/ Total revenues and other income	89,725		$ 89,869
The Kraft Heinz Company [Member]
Schedule Of Equity Method Investments [Line Items]
Assets					$ 90,274	$ 88,287
Liabilities					$ 40,669	$ 38,962
Sales/ Total revenues and other income	5,999		6,411
Net earnings attributable to common shareholders	$ 712		$ 801
Occidental Petroleum Corporation [Member]
Schedule Of Equity Method Investments [Line Items]
Assets		85,445					$ 85,803
Liabilities		50,965					$ 50,869
Sales/ Total revenues and other income		6,837		$ 7,529
Net earnings attributable to common shareholders		$ (297)		$ 1,029