Unaudited Condensed Consolidated Statement of Operations Statement (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenues	$ 625,505	$ 597,372	$ 1,277,857	$ 1,199,878
Costs and expenses	(499,684)	(469,183)	(992,436)	(944,122)
Gross profits	125,821	128,189	285,421	255,756
General and administrative expenses	(31,162)	(29,558)	(62,028)	(55,517)
Losses (gains) on divestitures and impairment charges, net	(5,545)	1,058	(6,514)	568
Operating income	89,114	99,689	216,879	200,807
Interest expense	(32,740)	(33,894)	(65,509)	(67,482)
Gains on early extinguishment of debt, net	468	0	468	0
Other (expense) income, net	(699)	(2,221)	(1,683)	1,684
Income before income taxes	56,143	63,574	150,155	135,009
Provision for income taxes	(21,708)	(25,935)	(56,997)	(49,055)
Net income	34,435	37,639	93,158	85,954
Net income attributable to noncontrolling interests	(820)	(563)	(1,922)	(853)
Net income attributable to common stockholders	$ 33,615	$ 37,076	$ 91,236	$ 85,101
Basic earnings per share:
Net income attributable to common stockholders, basic	$ 0.16	$ 0.17	$ 0.43	$ 0.39
Basic weighted average number of shares	211,821	215,898	211,602	218,015
Diluted earnings per share:
Net income attributable to common stockholders, diluted	$ 0.16	$ 0.17	$ 0.42	$ 0.39
Diluted weighted average number of shares	215,946	218,906	215,603	221,058
Dividends declared per share	$ 0.07	$ 0.06	$ 0.13	$ 0.11