Unaudited Condensed Consolidated Statement of Operations Statement - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Unaudited Condensed Consolidated Statement of Operations [Abstract]
Revenue	$ 773,242	$ 751,396	$ 1,550,952	$ 1,500,615
Costs and expenses	(589,797)	(589,407)	(1,190,342)	(1,175,703)
Operating profit	183,445	161,989	360,610	324,912
General and administrative expenses	(40,590)	(36,849)	(83,094)	(75,753)
Gains (losses) on divestitures and impairment charges, net	753	(30,641)	5,688	(30,988)
Operating income	143,608	94,499	283,204	218,171
Interest expense	(42,083)	(39,398)	(82,719)	(82,480)
Loss on early extinguishment of debt	0	(21,898)	0	(22,479)
Other expense, net	(7)	(564)	(441)	(806)
Income before income taxes	101,518	32,639	200,044	112,406
(Provision for) benefit from income taxes	(32,956)	(16,746)	43,267	(49,059)
Net Income	68,562	15,893	243,311	63,347
Net income attributable to noncontrolling interests	(81)	(273)	(128)	(282)
Net income attributable to common stockholders	$ 68,481	$ 15,620	$ 243,183	$ 63,065
Basic earnings per share:
Net income attributable to common stockholders, basic	$ 0.37	$ 0.08	$ 1.29	$ 0.32
Basic weighted average number of shares	187,597	193,806	187,927	194,366
Diluted earnings per share:
Net income attributable to common stockholders, diluted	$ 0.36	$ 0.08	$ 1.26	$ 0.32
Diluted weighted average number of shares	192,138	196,718	192,511	197,463
Dividends declared per share	$ 0.15	$ 0.13	$ 0.28	$ 0.25