CONDENSED COMBINED DEBTOR-IN-POSSESSION FINANCIAL INFORMATION - Debtors' Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Income Statements, Captions [Line Items]
Revenue	$ 1,772,525	$ 1,582,765	$ 1,600,842	$ 1,369,648	$ 1,713,161	$ 1,536,757	$ 1,589,637	$ 1,328,876	$ 6,325,780	$ 6,168,431	$ 6,251,000
Direct operating expenses	663,688	630,264	636,641	602,355	656,219	623,741	616,221	572,543	2,532,948	2,468,724	2,395,037
Selling, general and administrative expenses	514,269	457,757	451,490	472,987	505,131	438,796	447,509	450,786	1,896,503	1,842,222	1,726,118
Corporate expenses	94,665	84,193	79,626	78,734	78,411	77,967	77,158	78,362	337,218	311,898	341,072
Depreciation and amortization	111,125	120,700	147,644	151,434	157,645	149,749	147,795	146,106	530,903	601,295	635,227
Impairment charges	0	40,922	0	0	2,568	7,631	0	0	40,922	10,199	8,000
Other operating income (expense), net	(1,556)	(1,637)	(289)	(3,286)	10,919	(13,215)	6,916	31,084	(6,768)	35,704	353,556
Operating income (loss)	387,222	247,292	285,152	60,852	324,106	225,658	307,870	112,163	980,518	969,797	1,499,102
Interest expense (excludes contractual interest of $1,189,132 for the year ended December 31, 2018)	97,679	99,255	107,600	418,397	475,317	470,250	463,232	455,337	722,931	1,864,136	1,850,119
Equity in earnings (loss) of nonconsolidated affiliates	729	172	(38)	157	(615)	(2,238)	240	(242)	1,020	(2,855)	(16,733)
Gain on extinguishment of debt	0	0	0	100	1,271	0	0	0	100	1,271	157,556
Other expense, net	(23,352)	(6,182)	(28,279)	(1,063)	(6,517)	50	1,647	(15,374)	(58,876)	(20,194)	(86,009)
Income (loss) before income taxes	224,071	89,552	80,495	(550,406)	(157,072)	(246,780)	(153,475)	(358,790)	(156,288)	(916,117)	(296,203)
Income tax expense	(837)	17,769	146,785	(117,366)	(507,549)	2,051	17,408	30,684	46,351	(457,406)	(49,631)
Consolidated net income (loss)	$ 224,908	$ 71,783	$ (66,290)	$ (433,040)	$ 350,477	$ (248,831)	$ (170,883)	$ (389,474)	(202,639)	$ (458,711)	$ (246,572)
Debtors
Condensed Income Statements, Captions [Line Items]
Revenue									3,577,742
Direct operating expenses									1,056,315
Selling, general and administrative expenses									1,356,108
Corporate expenses									188,937
Depreciation and amortization									210,914
Impairment charges									33,151
Other operating income (expense), net									(9,260)
Operating income (loss)									723,057
Interest expense (excludes contractual interest of $1,189,132 for the year ended December 31, 2018)									357,181
Equity in earnings (loss) of nonconsolidated affiliates									(140)
Gain on extinguishment of debt									5,667
Investment Income, Dividend									28,564
Other expense, net									(22,776)
Reorganization items, net									356,119
Income (loss) before income taxes									21,072
Income tax expense									13,056
Consolidated net income (loss)									$ 8,016