Condensed Consolidating Financial Statements (Income Statement) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Condensed Income Statements, Captions [Line Items]
Revenues, net	$ 710,545	$ 684,832	$ 1,430,734	$ 1,391,411
Operating expenses
Technical and operating (excluding depreciation and amortization)	334,845	305,492	633,457	576,537
Selling, general and administrative	162,273	179,366	325,982	336,644
Restructuring (credit) expense	(81)	389	2,623	354
Depreciation and amortization	20,606	21,553	44,099	41,185
Impairment charges	17,112	0	17,112	0
Total operating expenses	534,755	506,800	1,023,273	954,720
Operating income	175,790	178,032	407,461	436,691
Other income (expense):
Interest expense, net	(26,951)	(30,336)	(53,958)	(61,364)
Share of affiliates' income	0	0	0	0
Loss on extinguishment of debt	0	(9)	0	(48,343)
Miscellaneous, net	18,980	(24,910)	30,028	(25,599)
Nonoperating Income (Expense)	(7,971)	(55,255)	(23,930)	(135,306)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	167,819	122,777	383,531	301,385
Income tax expense	(60,193)	(39,390)	(133,275)	(97,933)
Net income including noncontrolling interests	107,626	83,387	250,256	203,452
Net Income (Loss) Attributable to Noncontrolling Interest	(5,028)	(6,212)	(11,442)	(12,832)
Net Income (Loss) Attributable to Parent	102,598	77,175	238,814	190,620
Consolidation, Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Revenues, net	(5,432)	(2,390)	(7,757)	(4,874)
Operating expenses
Technical and operating (excluding depreciation and amortization)	(777)	(694)	(1,536)	(1,377)
Selling, general and administrative	(4,988)	(1,450)	(6,439)	(3,254)
Restructuring (credit) expense	0	0	0	0
Depreciation and amortization	0	0	0	0
Impairment charges	0		0
Total operating expenses	(5,765)	(2,144)	(7,975)	(4,631)
Operating income	333	(246)	218	(243)
Other income (expense):
Interest expense, net	0	0	0	0
Share of affiliates' income	(190,429)	(121,134)	(429,348)	(368,033)
Loss on extinguishment of debt		0		0
Miscellaneous, net	(333)	246	(218)	243
Nonoperating Income (Expense)	(190,762)	(120,888)	(429,566)	(367,790)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	(190,429)	(121,134)	(429,348)	(368,033)
Income tax expense	0	0	0	0
Net income including noncontrolling interests	(190,429)	(121,134)	(429,348)	(368,033)
Net Income (Loss) Attributable to Noncontrolling Interest	0	0	0	0
Net Income (Loss) Attributable to Parent	(190,429)	(121,134)	(429,348)	(368,033)
Parent Company [Member]
Condensed Income Statements, Captions [Line Items]
Revenues, net	0	0	0	0
Operating expenses
Technical and operating (excluding depreciation and amortization)	0	0	0	0
Selling, general and administrative	0	0	0	0
Restructuring (credit) expense	0	0	0	0
Depreciation and amortization	0	0	0	0
Impairment charges	0		0
Total operating expenses	0	0	0	0
Operating income	0	0	0	0
Other income (expense):
Interest expense, net	(29,733)	(30,172)	(59,145)	(60,742)
Share of affiliates' income	184,748	142,131	420,522	388,178
Loss on extinguishment of debt		(9)		(48,343)
Miscellaneous, net	(230)	(170)	(343)	(251)
Nonoperating Income (Expense)	154,785	111,780	361,034	278,842
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	154,785	111,780	361,034	278,842
Income tax expense	(52,187)	(34,605)	(122,220)	(88,222)
Net income including noncontrolling interests	102,598	77,175	238,814	190,620
Net Income (Loss) Attributable to Noncontrolling Interest	0	0	0	0
Net Income (Loss) Attributable to Parent	102,598	77,175	238,814	190,620
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Revenues, net	536,302	519,955	1,115,684	1,074,484
Operating expenses
Technical and operating (excluding depreciation and amortization)	240,150	223,254	461,904	414,032
Selling, general and administrative	116,423	130,383	236,104	245,894
Restructuring (credit) expense	(45)	112	2,659	42
Depreciation and amortization	10,123	9,952	20,327	20,027
Impairment charges	0		0
Total operating expenses	366,651	363,701	720,994	679,995
Operating income	169,651	156,254	394,690	394,489
Other income (expense):
Interest expense, net	10,165	9,538	19,988	18,831
Share of affiliates' income	5,681	(20,997)	8,826	(20,145)
Loss on extinguishment of debt		0		0
Miscellaneous, net	1,898	(190)	2,329	(213)
Nonoperating Income (Expense)	17,744	(11,649)	31,143	(1,527)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	187,395	144,605	425,833	392,962
Income tax expense	(2,647)	(2,474)	(5,311)	(4,784)
Net income including noncontrolling interests	184,748	142,131	420,522	388,178
Net Income (Loss) Attributable to Noncontrolling Interest	0	0	0	0
Net Income (Loss) Attributable to Parent	184,748	142,131	420,522	388,178
Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Revenues, net	179,675	167,267	322,807	321,801
Operating expenses
Technical and operating (excluding depreciation and amortization)	95,472	82,932	173,089	163,882
Selling, general and administrative	50,838	50,433	96,317	94,004
Restructuring (credit) expense	(36)	277	(36)	312
Depreciation and amortization	10,483	11,601	23,772	21,158
Impairment charges	17,112		17,112
Total operating expenses	173,869	145,243	310,254	279,356
Operating income	5,806	22,024	12,553	42,445
Other income (expense):
Interest expense, net	(7,383)	(9,702)	(14,801)	(19,453)
Share of affiliates' income	0	0	0	0
Loss on extinguishment of debt		0		0
Miscellaneous, net	17,645	(24,796)	28,260	(25,378)
Nonoperating Income (Expense)	10,262	(34,498)	13,459	(44,831)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	16,068	(12,474)	26,012	(2,386)
Income tax expense	(5,359)	(2,311)	(5,744)	(4,927)
Net income including noncontrolling interests	10,709	(14,785)	20,268	(7,313)
Net Income (Loss) Attributable to Noncontrolling Interest	(5,028)	(6,212)	(11,442)	(12,832)
Net Income (Loss) Attributable to Parent	$ 5,681	$ (20,997)	$ 8,826	$ (20,145)