Derivative Instruments - Effect of Cash Flow Hedges on Statement of Income (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) on cash flow hedging relationships	$ 0	$ 0
Component of the derivative instruments’ gains or losses was excluded from the assessment of hedge effectiveness	0	0
Commodity contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) on cash flow hedging relationships	(700,000)	19,100,000
Derivatives designated as hedging instruments: \| Commodity contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) on cash flow hedging relationships	700,000	(19,100,000)
Cost of sales \| Commodity contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	600,000	$ 15,100,000
Cash flow hedges to be reclassified into cost of goods sold over the next 12 months	3,300,000
Cost of sales \| Derivatives designated as hedging instruments: \| Commodity contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Component of the derivative instruments’ gains or losses was excluded from the assessment of hedge effectiveness	$ 0

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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The net gain (loss) relating to components of the gain (loss) on the cash flow hedging instrument excluded from the assessment of cash flow hedge effectiveness. Recognized in earnings.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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