Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Property and Equipment
Property and equipment, gross	$ 54,204	$ 49,463
Less accumulated depreciation	(40,659)	(36,337)
Property and equipment, net	13,545	13,126
Computer and other related equipment
Property and Equipment
Property and equipment, gross	12,085	10,859
Purchased and internally developed software
Property and Equipment
Property and equipment, gross	33,256	29,758
Furniture and fixtures
Property and Equipment
Property and equipment, gross	1,487	1,470
Leasehold improvements
Property and Equipment
Property and equipment, gross	6,795	6,795
Machinery and related equipment
Property and Equipment
Property and equipment, gross	$ 581	$ 581

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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