Derivatives and Fair Value of Financial Instruments-Derivatives (Details) lb in Millions, gal in Millions, bu in Millions, $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2018 USD ($) lb gal bu	Dec. 31, 2017 USD ($) lb gal bu
Equity future contracts
Derivative commodity instruments
Notional amounts \| $	$ 371	$ 0
Net commodity purchase contracts \| Grain
Derivative commodity instruments
Nonmonetary notional amount \| bu	30	29
Net commodity purchase contracts \| Hogs
Derivative commodity instruments
Nonmonetary notional amount	26
Net commodity purchase contracts \| Soybean oil
Derivative commodity instruments
Nonmonetary notional amount	91	1
Net commodity sale contracts \| Hogs
Derivative commodity instruments
Nonmonetary notional amount		13
Net commodity sale contracts \| Heating oil
Derivative commodity instruments
Nonmonetary notional amount \| gal	17	7
Foreign currencies
Derivative commodity instruments
Notional amounts \| $	$ 70	$ 20

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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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

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Nominal mass used to calculate payments on a derivative instrument.

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- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

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