Intangible Assets and Goodwill - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Finite Lived Intangible Assets [Line Items]
Amortization expense related to capitalized internal-use software	$ 3,700	$ 5,900
Amortization expense	1,025	$ 1,092
Capitalized internal-use software, net	33,710		$ 33,280
Capitalized Internal-Use Software Net in Development Phase [Member]
Finite Lived Intangible Assets [Line Items]
Capitalized internal-use software, net	$ 16,900

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount of expense for amortization of capitalized computer software costs.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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