Other Comprehensive Income (Loss) (Components And Allocated Tax Effects Of Other Comprehensive Income (Loss)) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Other Comprehensive Income (Loss) Components and Tax Effects [Line Items]
Available-for-sale Securities, Change in Net Unrealized Holding Gain (Loss) before Taxes	$ 68	$ 11
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, before Tax	0	(89)
Other comprehensive income (loss)	(19,251)	87,005
Less other comprehensive income attributable to noncontrolling interest	(454)	58
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax	27	(3)
Net unrealized gain (loss) on hedging instruments, tax expense (benefit)	(7,302)	33,743
Net change in post-retirement benefit obligations, tax expense (benefit)		(35)
Other comprehensive income, tax expense	(7,275)	33,705
Net unrealized gain on marketable securities, after tax	41	14
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(19,319)	87,083
Net unrealized gain (loss) on hedging instruments, after tax	(12,017)	53,340
Net Change in Post-retirement Benefit Obligations, After Tax		(54)
Other comprehensive income, after tax	(11,976)	53,300
Less other comprehensive income attributable to noncontrolling interest, after tax	(454)	58
Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	(18,797)	86,947
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(7,275)	33,705
Other Comprehensive Income (Loss) Change in Current Period	$ (11,522)	$ 53,242