PROPERTY AND EQUIPMENT (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property and equipment	$ 52,451	$ 76,846
Less: Accumulated Depreciation	(31,378)	(40,705)
Property and Equipment, net	21,073	36,141	$ 38,921
Aircraft
Property, Plant and Equipment [Line Items]
Property and equipment	12,474	27,567
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment	21,983	23,506
Manufacturing Equipment
Property, Plant and Equipment [Line Items]
Property and equipment	6,116	7,778
Software Development Costs
Property, Plant and Equipment [Line Items]
Property and equipment	2,111	2,111
Office Equipment
Property, Plant and Equipment [Line Items]
Property and equipment	$ 9,767	$ 15,884