Divestiture - Narrative (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Jul. 28, 2019	Dec. 28, 2019	Sep. 28, 2019	Sep. 28, 2019	Sep. 29, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from sale of businesses				$ 1,332	$ 0
Debt repurchase amount			$ 1,000	1,000
Income taxes paid		$ 260		$ 211	$ 163
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]
Cash proceeds from sale 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
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