Derivative Commodity Instruments (Impact Of Derivative Instruments Designated As Fair Value Hedges) (Details) (Designated As Fair Value Hedges [Member], Cost of Sales [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commodity Forward Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	$ 0	$ (303)	$ 17,163
Firm Commitment Hedged Items [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	$ 0	$ 143	$ (18,394)