Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of expense charged against earnings to allocate the cost of tangible and intangible assets over their remaining economic lives, classified as other.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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PROPERTY AND EQUIPMENT, NET (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Property and equipment, net
Property and equipment, gross	$ 397,259		$ 397,259		$ 369,086
Less: accumulated depreciation and amortization	(156,601)		(156,601)		(138,810)
Property and equipment, net	240,658		240,658		230,276
Total depreciation and amortization expense	11,200	$ 8,600	22,200	$ 16,800
Land
Property and equipment, net
Property and equipment, gross	44,261		44,261		47,373
Leasehold improvements
Property and equipment, net
Property and equipment, gross	3,278		3,278		3,109
Furniture and fixtures
Property and equipment, net
Property and equipment, gross	6,732		6,732		6,461
Office and computer equipment
Property and equipment, net
Property and equipment, gross	17,683		17,683		14,506
Computer software
Property and equipment, net
Property and equipment, gross	3,334		3,334		3,650
Equipment
Property and equipment, net
Property and equipment, gross	165,861		165,861		148,434
Buildings
Property and equipment, net
Property and equipment, gross	116,143		116,143		107,374
Vehicles
Property and equipment, net
Property and equipment, gross	$ 39,967		$ 39,967		$ 38,179