Equity Investees (Schedule Of Operations For Equity Investees) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Equity Method Investments and Joint Ventures [Abstract]
Revenues	$ 40,740	$ 37,518
Operating income	21,100	19,396
Net income	$ 20,455	$ 18,675

The amount of income (loss) from continuing operations before extraordinary items reported by an equity method investment of the entity.

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The amount of net income (loss) reported by an equity method investment of the entity.

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