Equity Investees (Schedule Of Operations For Equity Investees) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Equity Method Investments and Joint Ventures [Abstract]
Revenues	$ 49,239	$ 39,799	$ 135,507	$ 113,769
Operating income	28,419	19,810	75,946	53,597
Net income	$ 27,725	$ 19,196	$ 73,928	$ 51,553