Equity Investees (Schedule Of Operations For Equity Investees) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Equity Method Investments and Joint Ventures [Abstract]
Revenues	$ 45,528	$ 36,452	$ 86,268	$ 73,970
Operating income	26,427	14,391	47,527	33,787
Net income	$ 25,748	$ 13,682	$ 46,203	$ 32,357