Property, Equipment and Software, net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Total property, equipment and software, at cost	$ 66,795	$ 57,280
Less accumulated depreciation and amortization	(46,463)	(40,580)
Property, equipment and software, net	$ 20,332	16,700
Computer/office equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Life	36 months
Total property, equipment and software, at cost	$ 17,292	15,107
Capitalized internal-use software
Property, Plant and Equipment [Line Items]
Estimated Useful Life	36 months
Total property, equipment and software, at cost	$ 36,733	30,412
Amortization expense	4,000	4,400	$ 4,900
Impairment expense	3,200
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property, equipment and software, at cost	$ 12,770	11,761
Computer and leasehold improvements
Property, Plant and Equipment [Line Items]
Computer and leasehold improvements disposals		$ 5,700

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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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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