Equipment and Leasehold Improvements - Schedule of Equipment and Leasehold Improvements, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Equipment and Leasehold Improvements, Net
Total	$ 28,851	$ 24,387
Less accumulated depreciation and amortization	(16,847)	(13,929)
Equipment and leasehold improvements, net	12,004	10,458
Office Equipment
Equipment and Leasehold Improvements, Net
Total	12,300	9,639
Furniture and Fixtures
Equipment and Leasehold Improvements, Net
Total	3,954	3,424
Leasehold Improvements
Equipment and Leasehold Improvements, Net
Total	$ 12,597	$ 11,324

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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