Derivatives and Fair Value of Financial Instruments - Instruments and Agreements (Details) lb in Millions, gal in Millions, bu in Millions, $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) lb bu agreement	Dec. 31, 2019 USD ($) bu lb gal
Net commodity purchase contracts \| Hogs
Derivative commodity instruments
Nonmonetary notional amount \| lb	2
Net commodity purchase contracts \| Grain
Derivative commodity instruments
Nonmonetary notional amount \| bu	26	17
Net commodity sale contracts \| Heating oil
Derivative commodity instruments
Nonmonetary notional amount \| gal		12
Net commodity sale contracts \| Soybean oil
Derivative commodity instruments
Nonmonetary notional amount \| lb	56	132
Foreign currencies
Derivative commodity instruments
Notional amounts	$ 49	$ 78
Equity futures contract
Derivative commodity instruments
Notional amounts	3	$ 0
Interest rate swaps
Derivative commodity instruments
Notional amounts	$ 400
Number of derivative instruments entered into \| agreement	3
Interest rate swaps \| Weighted Average
Derivative commodity instruments
Fixed rate interest	0.26%

The number of derivative instruments entered into by the entity.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Nominal number of units used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

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- Definition

Fixed interest rate that will be received or paid upon exercise of the interest rate swaption contract.

+ References

No definition available.

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