CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Parent [Member]	Member's Deficiency	Accumulated Deficit	Treasury Stock	Accumulated Other Comprehensive Income	Noncontrolling Interests	Common Class A Common Stock	Common Class B Common Stock
Beginning balance at Dec. 31, 2020	$ (1,203,139)	$ (1,141,030)	$ 0	$ (985,641)	$ (163,866)	$ 3,646	$ (62,109)	$ 2,972	$ 1,859
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent, Total	274,136	274,136		274,136
Net Income (Loss) Attributable to Noncontrolling Interest	(4,403)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(6,356)	(6,356)				6,356
Foreign currency translation adjustment, net of income taxes	619	619				619
Share-based compensation expense (equity classified)	27,964	27,964		27,964
Redeemable equity vested	20,131	20,131		20,131
Change in redeemable equity	2,528	2,528		2,528
Class A shares acquired through share repurchase program and retired	(522,673)	(522,673)		(522,521)				(152)
Conversion of Class B to Class A shares								1	(1)
Stock Issued During Period, Value, New Issues	2,044	2,044		2,037	6			1
Other	58	(4,244)		(4,244)			4,302
Ending balance at Mar. 31, 2021	(1,387,573)	(1,334,169)	0	(1,185,610)	(163,860)	10,621	(53,404)	2,822	1,858
Beginning balance at Dec. 31, 2020	(1,203,139)	(1,141,030)	0	(985,641)	(163,866)	3,646	(62,109)	2,972	1,859
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent, Total	471,796
Net Income (Loss) Attributable to Noncontrolling Interest	(7,677)
Foreign currency translation adjustment, net of income taxes	479
Ending balance at Jun. 30, 2021	(1,348,994)	(1,298,940)	0	(1,315,080)	0	11,569	(50,054)	2,713	1,858
Beginning balance at Mar. 31, 2021	(1,387,573)	(1,334,169)	0	(1,185,610)	(163,860)	10,621	(53,404)	2,822	1,858
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent, Total	197,660	197,660		197,660
Net Income (Loss) Attributable to Noncontrolling Interest	(3,274)						(3,274)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(1,088)	(1,088)				1,088
Foreign currency translation adjustment, net of income taxes	(140)	(140)				(140)
Share-based compensation expense (equity classified)	27,385	27,385		27,385
Redeemable equity vested	3,618	3,618		3,618
Change in redeemable equity	(514)	(514)		(514)
Class A shares acquired through share repurchase program and retired	(202,845)	(202,845)		(202,787)				(58)
Conversion of Class B to Class A shares									0
Stock Issued During Period, Value, New Issues	8,885	8,885		(488)	9,365			8
Other	168	92		92			76
Ending balance at Jun. 30, 2021	(1,348,994)	(1,298,940)	0	(1,315,080)	0	11,569	(50,054)	2,713	1,858
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Retirement of Treasury Stock in connection with Neptune Acquisition				(154,436)	154,495			(59)
Accumulated deficit	(848,836)
Beginning balance at Dec. 31, 2021	(870,902)	(819,788)	18,005	(848,836)	0	6,497	(51,114)	2,703	1,843
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent, Total	196,551	196,551		196,551
Net Income (Loss) Attributable to Noncontrolling Interest	(5,590)						(5,590)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(1,843)	(1,843)				1,843
Foreign currency translation adjustment, net of income taxes	(170)	(170)				(170)
Share-based compensation expense (equity classified)	40,512	40,512	40,512	0
Stock Issued During Period, Value, New Issues	10	10	10	0	0			0
Ending balance at Mar. 31, 2022	(626,566)	(581,042)	58,527	(652,285)	0	8,170	(45,524)	2,703	1,843
Beginning balance at Dec. 31, 2021	(870,902)	(819,788)	18,005	(848,836)	0	6,497	(51,114)	2,703	1,843
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent, Total	302,725
Net Income (Loss) Attributable to Noncontrolling Interest	(12,956)
Foreign currency translation adjustment, net of income taxes	(109)
Ending balance at Jun. 30, 2022	(474,634)	(436,476)	100,213	(546,111)	0	4,876	(38,158)	2,703	1,843
Beginning balance at Mar. 31, 2022	(626,566)	(581,042)	58,527	(652,285)	0	8,170	(45,524)	2,703	1,843
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent, Total	106,174	106,174
Net Income (Loss) Attributable to Noncontrolling Interest	(7,366)						(7,366)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	3,355	3,355				(3,355)
Foreign currency translation adjustment, net of income taxes	61	61				61
Share-based compensation expense (equity classified)	41,680	41,680	41,680	0
Stock Issued During Period, Value, New Issues	6	6	6	0	0			0
Ending balance at Jun. 30, 2022	(474,634)	$ (436,476)	$ 100,213	$ (546,111)	$ 0	$ 4,876	$ (38,158)	$ 2,703	$ 1,843
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated deficit	$ (546,111)