Derivatives and Fair Value of Financial Instruments-Derivatives (Details) lb in Millions, gal in Millions, bu in Millions, $ in Millions	9 Months Ended	12 Months Ended
Sep. 28, 2019 USD ($) lb gal bu	Dec. 31, 2018 USD ($) lb gal bu
Equity future contracts
Derivative commodity instruments
Notional amounts \| $	$ 2	$ 97
Net commodity purchase contracts \| Grain
Derivative commodity instruments
Nonmonetary notional amount \| bu	32	33
Net commodity purchase contracts \| Hogs
Derivative commodity instruments
Nonmonetary notional amount	34
Net commodity purchase contracts \| Soybean oil
Derivative commodity instruments
Nonmonetary notional amount		8
Net commodity sale contracts \| Hogs
Derivative commodity instruments
Nonmonetary notional amount		26
Net commodity sale contracts \| Soybean oil
Derivative commodity instruments
Nonmonetary notional amount	84
Net commodity sale contracts \| Heating oil
Derivative commodity instruments
Nonmonetary notional amount \| gal	4	7
Foreign currencies
Derivative commodity instruments
Notional amounts \| $	$ 34	$ 82

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+ 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=109980867&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=109980867&loc=SL5579245-113959

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