Divestiures, West Africa Investments and Acquisitions Divestiture (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
	Jul. 28, 2019	Dec. 28, 2019	Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018	Sep. 28, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses			$ 7	$ (1,332)	$ 0
Debt repurchase amount						$ 1,000
Income taxes paid		$ 255	281	537	$ 188
Cookies, fruit and fruit flavored snacks, pie crusts and ice cream cones businesses
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses	$ (1,300)
Net assets	1,300
Cookies, fruit and fruit flavored snacks, pie crusts and ice cream cones businesses | North America
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses	(1,300)
Net assets	$ 1,300
Cookies, fruit and fruit flavored snacks, pie crusts and ice cream cones businesses | Other income (expense)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on disposition of business				38
Disposition related transaction costs				14
Cookies, fruit and fruit flavored snacks, pie crusts and ice cream cones businesses | Other income (expense) | North America
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses			$ 4
U.S. pension and nonpension postretirement plans | Cookies, fruit and fruit flavored snacks, pie crusts and ice cream cones businesses
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Curtailment gain				$ 17