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Commitments and Contingencies - Numbers of Items (Details) $ in Millions					12 Months Ended
	Jun. 28, 2018 item plaintiff	May 15, 2018 USD ($)	Apr. 27, 2018 USD ($)	Mar. 20, 2018 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Contingencies
Assets					$ 6,399	$ 6,349
Pork Product Purchasers \| Pending Litigation
Contingencies
Number of plaintiffs \| plaintiff	12
Number of consolidated putative class actions \| item	3
Cereoil
Contingencies
Percentage of ownership					45.00%
Cereoil \| Cereoil Bankruptcy Trustee - Case One \| Pending Litigation
Contingencies
Damages sought				$ 22
Cereoil \| Cereoil Bankruptcy Trustee - Case Two \| Pending Litigation
Contingencies
Damages sought			$ 23
Total liabilities			53
Assets			$ 30
Pending claim in bankruptcy proceeding, included the net indebtedness of Cereoil					$ 10
Nolston
Contingencies
Percentage of ownership					45.00%
Nolston \| Nolston Bankruptcy Trustee \| Pending Litigation
Contingencies
Damages sought		$ 14
Total liabilities		29
Assets		$ 15