Equity Investments (Tables)

12 Months Ended

Dec. 31, 2011

Equity Investments [Abstract]

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

	December 31,
	2011		2010
Current assets	$	233,496	$	220,881
Noncurrent assets		790,125		771,646
Total assets	$	1,023,621	$	992,527
Current liabilities	$	82,687	$	83,985
Noncurrent liabilities		2,094		2,198
Members’ equity		938,672		905,006
Noncontrolling interests		168		1,338
Total liabilities and equity	$	1,023,621	$	992,527

	Year Ended December 31,
	2011		2010		2009
Revenues	$	1,455,991	$	1,418,432	$	1,401,095
Operating costs and expenses	$	1,294,057	$	1,268,075	$	1,252,714
Income from continuing operations before taxes	$	162,124	$	150,640	$	148,343