Derivatives (Fair Value Of Derivative Instruments And Locations In Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Current derivative assets	$ 515	$ 16,552
Total derivatives assets	515	16,552
Current portion of derivative liabilities	5,561	1,948
Non-current derivative liabilities	0	562
Total derivative liabilities	5,561	2,510
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Current derivative assets	0	13,674
Non-current derivative assets	0	0
Total derivatives assets	0	13,674
Current portion of derivative liabilities	0	1,005
Non-current derivative liabilities	0	0
Total derivative liabilities	0	1,005
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Current derivative assets	515	2,878
Non-current derivative assets	0	0
Total derivatives assets	515	2,878
Current portion of derivative liabilities	5,561	943
Non-current derivative liabilities	0	562
Total derivative liabilities	$ 5,561	$ 1,505