Rate Reconciliation Between Amount of Income Tax Provision (Benefit) at Federal Rate and Provision (Benefit) from Taxes on Income (Loss) Before Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income tax benefit computed at the federal rate of 35%									$ (228,701)	$ (117,582)	$ (109,900)
Increase (reduction) in income taxes resulting from:
State and local income taxes (benefit), net of federal income tax									(8,511)	695	6,103
Non-controlling interest									8,869	567	1,257
Unrecognized tax benefits									1,690	241	6,985
Valuation allowance									80,800		(11,205)
Change in position of prior year foreign tax credits									8,410
Non-deductible executive compensation									929	1,330	645
Foreign Earnings (rate differential)									6,287	37,384	235
US Tax Reform / rate reduction									34,205
Other, net									45	(760)	1,979
Total benefit	$ (66,757)	$ (29,606)	$ (5,501)	$ 5,887	$ (103,282)	$ 9,433	$ 6,888	$ 8,836	$ (95,977)	$ (78,125)	$ (103,901)