PROPERTY AND EQUIPMENT - Schedule of property and equipment, net (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property and Equipment
Total gross property and equipment	$ 49,342	$ 37,062
Accumulated depreciation	(17,979)	(13,887)
Total property and equipment, net	31,363	23,175
Computer equipment and capitalized software
Property and Equipment
Total gross property and equipment	28,425	22,847
Leasehold improvements
Property and Equipment
Total gross property and equipment	7,751	4,651
Furniture and other equipment
Property and Equipment
Total gross property and equipment	3,993	1,935
Aircraft and automobile
Property and Equipment
Total gross property and equipment	2,621	2,621
Projects in progress
Property and Equipment
Total gross property and equipment	$ 6,552	$ 5,008

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 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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