Derivative Instruments And Hedging Activities (Impact Of Non Designated Derivative Instruments On Income Statement) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Gain (Loss) Recognized in Income on Derivatives	$ 850	$ (381)	$ 1,014	$ (234)
Natural Gas Contracts [Member] | Hedge Ineffectiveness And Non Hedge Gain On Commodity Derivative Contracts [Member]
Gain (Loss) Recognized in Income on Derivatives	633		633
Foreign Exchange Contracts [Member] | Other Expense [Member]
Gain (Loss) Recognized in Income on Derivatives	$ 217	$ (381)	$ 381	$ (234)