Derivative Instruments And Hedging Activities (Impact Of Non Designated Derivative Instruments On Income Statement) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Earnings on Derivatives	$ 7	$ (15,443)
Oil And Natural Gas Commodity Contracts [Member] | Non Hedge Loss On Commodity Derivative Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Earnings on Derivatives		(14,113)
Interest Rate Swaps [Member] | Other Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Earnings on Derivatives		(86)
Foreign Exchange Contracts [Member] | Other Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Earnings on Derivatives	$ 7	$ (1,244)