Consolidated Statement of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Product Information [Line Items]
Revenue	$ 3,190,174	$ 3,095,031	$ 3,031,137
Costs and expenses	(2,429,852)	(2,372,252)	(2,354,287)
Operating profit	760,322	722,779	676,850
General and administrative expenses	(145,499)	(153,067)	(136,708)
Gains (losses) on divestitures and impairment charges, net	15,933	7,015	(26,819)
Hurricane expense, net	(97)	5,584	0
Operating income	630,659	571,143	513,323
Interest expense	(181,556)	(169,125)	(162,093)
Losses on early extinguishment of debt, net	(10,131)	(274)	(22,503)
Other income (expense), net	2,760	(1,486)	(2,069)
Income before income taxes	441,732	400,258	326,658
Benefit from (provision for) income taxes	5,826	146,589	(149,353)
Net income	447,558	546,847	177,305
Net income attributable to noncontrolling interests	(350)	(184)	(267)
Net income attributable to common stockholders	$ 447,208	$ 546,663	$ 177,038
Basic earnings per share:
Net income attributable to common stockholders, basic	$ 2.45	$ 2.91	$ 0.92
Basic weighted average number of shares	182,447	187,630	193,086
Diluted earnings per share:
Net income attributable to common stockholders, diluted	$ 2.39	$ 2.84	$ 0.90
Diluted weighted average number of shares	186,972	192,246	196,042
Dividends declared per share	$ 0.68	$ 0.58
Product [Member]
Product Information [Line Items]
Revenue	$ 1,584,242	$ 1,525,747	$ 1,456,596
Costs and expenses	(811,574)	(794,725)	(776,411)
Service [Member]
Product Information [Line Items]
Revenue	1,374,380	1,356,665	1,345,528
Costs and expenses	(752,488)	(729,204)	(733,690)
Product and Service, Other [Member]
Product Information [Line Items]
Revenue	231,552	212,619	229,013
Costs and expenses	$ (865,790)	$ (848,323)	$ (844,186)