Derivative Commodity Instruments (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) lb gal	Dec. 31, 2018 USD ($) lb gal
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	93,000,000.0	50,000,000.0
Derivative, Nonmonetary Notional Amount, Volume \| gal	39,100,000	21,000,000.0
Derivative Liability, Current	$ 1,959	$ 315
Derivative Asset, Current	597	253
Cost of Sales [Member]
Derivative [Line Items]
Loss on Derivative Instruments, Pretax	3,335	315
Sales [Member]
Derivative [Line Items]
Gain on Derivative Instruments, Pretax	$ 836	$ 253

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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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.

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Nominal mass used to calculate payments on a derivative instrument.

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Nominal volume used to calculate payments on a derivative instrument.

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Aggregate gain on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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Aggregate loss on all derivative instruments charged against earnings during the period, before tax effects.

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