Derivative Financial Instruments (Schedule Of Gain Or Loss Recognized In Income And Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) on Derivative Instruments Not Designated in a Hedging Relationship	$ 6,888	$ (8,640)
Gains (Losses) Due to Ineffectiveness of Cash Flow Hedges	(133)
Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Net Income	4,982	2,134
Gains (Losses) from Fair Value Hedges of Inventory	1,437	910
Revenue [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) on Derivative Instruments Not Designated in a Hedging Relationship	(5,048)	(2,794)
Gains (Losses) Due to Ineffectiveness of Cash Flow Hedges	(133)
Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Net Income	4,152	245
Revenue (Effect of Change In Inventory Value) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) from Fair Value Hedges of Inventory	1,421	1,760
Revenue (Effect of Fair Value Hedge) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) from Fair Value Hedges of Inventory	(1,095)	(1,760)
Cost of Goods Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) on Derivative Instruments Not Designated in a Hedging Relationship	11,936	(5,846)
Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Net Income	830	1,889
Cost of Goods Sold (Effect of Change in Inventory Value) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) from Fair Value Hedges of Inventory	(1,928)	(4,898)
Cost of Goods Sold (Effect of Fair Value Hedge) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) from Fair Value Hedges of Inventory	$ 3,039	$ 5,808

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624177-113959

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1),(2)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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