Derivative Instruments (Schedule Of Fair Value Of Derivatives Designated As Cash Flow Hedges) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Derivative [Line Items]
Derivatives designated as cash flow hedges, Asset Derivatives, Fair Value	$ 9,521	$ 5,516
Derivatives designated as cash flow hedges, Liability Derivatives, Fair Value	3,420	3,391
Foreign Currency Derivatives [Member] | Other Receivables [Member]
Derivative [Line Items]
Derivatives designated as cash flow hedges, Asset Derivatives, Fair Value	3,716	4,412
Foreign Currency Derivatives [Member] | Other Payables [Member]
Derivative [Line Items]
Derivatives designated as cash flow hedges, Liability Derivatives, Fair Value	1,253	1,834
Commodity Derivative Contracts [Member] | Other Current Assets [Member]
Derivative [Line Items]
Derivatives designated as cash flow hedges, Asset Derivatives, Fair Value	5,805	1,104
Commodity Derivative Contracts [Member] | Other Current Liabilities [Member]
Derivative [Line Items]
Derivatives designated as cash flow hedges, Liability Derivatives, Fair Value	$ 2,167	$ 1,557