Revenues from Contracts with Customers (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Disaggregation Of Revenue [Line Items]
Receivables related to revenue from contracts with customers	$ 410.0	$ 469.3
Deferred revenue	17.6	$ 15.5
Deferred revenue, revenue recognized	4.9
Capitalized contract cost	3.6
Expenses related to capitalized costs to fulfill a contract	$ 2.4
Revenue \| Product Concentration Risk \| Sale of Beef, Pork and Beef By-Products
Disaggregation Of Revenue [Line Items]
Concentration risk, percentage	95.00%
National Beef \| Sale of Beef, Pork and Beef By-Products
Disaggregation Of Revenue [Line Items]
Period of payment due from delivery	7 days
Jefferies
Disaggregation Of Revenue [Line Items]
Revenue related to performance obligation satisfied	$ 11.7
Revenue associated with distribution services, a portion of which related to prior period	$ 4.6

Capitalized Contract Cost, Amortization

No definition available.

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- Definition

Capitalized Contract Cost, Net

+ References

No definition available.

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- Definition

Contract With Customer Receivables, Net

+ References

No definition available.

+ Details

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- Definition

Contract With Customer, Revenue Related to Performance Obligations Satisfied

+ References

No definition available.

+ Details

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- Definition

[Line Items] for Disaggregation Of Revenue [Table]

+ References

No definition available.

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- Definition

Period Of Payment Due From Delivery

+ References

No definition available.

+ Details

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- Definition

Revenues Associated With Distribution Services

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

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- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.3)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
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- Definition

Amount of revenue recognized that was previously reported as deferred or unearned revenue.

+ References

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- Details

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