CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Total Stockholders' Equity	Paid-in Capital	Retained Earnings (Accumulated Deficit)	Treasury Stock	Accumulated Other Comprehensive Income	Non-controlling Interest	Common Class A Common Stock	Common Class B Common Stock
Beginning balance at Dec. 31, 2017	$ 5,504,753	$ 5,503,214	$ 4,665,229	$ 840,636		$ (10,022)	$ 1,539	$ 2,470	$ 4,901
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to stockholders	(128,951)	(128,951)		(128,951)
Net loss (income) attributable to noncontrolling interests	2						2
Pension liability adjustments, net of income taxes	3,765	3,765				3,765
Share-based compensation expense	21,623	21,623	21,623
Change in redeemable equity	(3,347)	(3,347)	(3,347)
Other changes to equity	(859)	(859)	(859)
Ending balance at Mar. 31, 2018	5,396,986	5,395,445	4,682,646	713,848		(8,420)	1,541	2,470	4,901
Beginning balance at Dec. 31, 2017	5,504,753	5,503,214	4,665,229	840,636		(10,022)	1,539	2,470	4,901
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to stockholders	(226,806)
Net loss (income) attributable to noncontrolling interests	(147)
Foreign currency translation adjustment, net of income taxes	576
Ending balance at Jun. 30, 2018	3,867,193	3,859,806	3,856,682	6,191		(10,438)	7,387	4,928	2,443
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of ASU No. 2018-02 | ASU No. 2018-02				2,163		(2,163)
Beginning balance at Mar. 31, 2018	5,396,986	5,395,445	4,682,646	713,848		(8,420)	1,541	2,470	4,901
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to stockholders	(97,855)	(97,855)		(97,855)
Net loss (income) attributable to noncontrolling interests	(149)
Pension liability adjustments, net of income taxes	(74)
Foreign currency translation adjustment, net of income taxes	576
Share-based compensation expense	12,226	12,226	12,226
Redeemable equity vested	111,521	111,521	111,521
Change in redeemable equity	47,049	47,049	47,049
Conversion of Class B to Class A shares								2,458	(2,458)
Shares issued in connection with acquisition	(15,049)	(15,049)	61,049	(73,578)		(2,520)
Contributions from noncontrolling interests	5,995
Dividend payment	(1,499,935)	(1,499,935)	(963,711)	(536,224)
Ending balance at Jun. 30, 2018	3,867,193	3,859,806	3,856,682	6,191		(10,438)	7,387	4,928	2,443
Beginning balance at Dec. 31, 2018	3,680,236	3,670,941	3,423,803	251,830	$ 0	(11,783)	9,295	4,961	2,130
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to stockholders	(24,999)	(24,999)		(24,999)
Net loss (income) attributable to noncontrolling interests	(199)						(199)
Distributions from noncontrolling interests	(1,000)						(1,000)
Pension liability adjustments, net of income taxes	3,752	3,752				3,752
Foreign currency translation adjustment, net of income taxes	(181)	(181)				(181)
Share-based compensation expense	13,790	13,790	13,790
Redeemable equity vested	1,364	1,364	1,364
Change in redeemable equity	(61,696)	(61,696)	(61,696)
Class A shares acquired through share repurchase program and retired	(600,001)	(600,001)	(599,707)					(294)
Conversion of Class B to Class A shares								242	(242)
Ending balance at Mar. 31, 2019	3,011,066	3,002,970	2,777,554	226,831	0	(8,212)	8,096	4,909	1,888
Beginning balance at Dec. 31, 2018	3,680,236	3,670,941	3,423,803	251,830	0	(11,783)	9,295	4,961	2,130
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to stockholders	61,368
Net loss (income) attributable to noncontrolling interests	(156)
Foreign currency translation adjustment, net of income taxes	(423)
Ending balance at Jun. 30, 2019	2,533,764	2,525,625	2,220,348	313,198	0	(14,474)	8,139	4,681	1,872
Beginning balance at Mar. 31, 2019	3,011,066	3,002,970	2,777,554	226,831	0	(8,212)	8,096	4,909	1,888
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss attributable to stockholders	86,367	86,367		86,367
Net loss (income) attributable to noncontrolling interests	43						43
Pension liability adjustments, net of income taxes	(6,019)	(6,019)				(6,019)
Foreign currency translation adjustment, net of income taxes	(243)	(243)				(243)
Share-based compensation expense	16,077	16,077	16,077
Redeemable equity vested	61,702	61,702	61,702
Change in redeemable equity	(46,294)	(46,294)	(46,294)
Class A shares acquired through share repurchase program and retired	(599,952)	(599,952)	(599,703)					(249)
Conversion of Class B to Class A shares								16	(16)
Issuance of stock	244	244	244
Shares issued in connection with acquisition	10,773	10,773	10,768					5
Ending balance at Jun. 30, 2019	$ 2,533,764	$ 2,525,625	$ 2,220,348	$ 313,198	$ 0	$ (14,474)	$ 8,139	$ 4,681	$ 1,872