Equity Investments (Tables)

6 Months Ended

Jun. 30, 2011

Equity Investments [Abstract]

Summarized combined financial information of entities in which Company owns equity interest

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2011		2010		2011		2010
Revenues	$	373,448	$	358,586	$	746,039	$	716,065
Operating costs and expenses		334,765		321,457		652,752		645,977
Income from continuing operations before taxes		38,652		37,113		93,236		70,045