Goodwill and Intangible Assets - Narrative (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 97,866		$ 97,866		$ 88,420
Amortization expense	$ 1,900	$ 1,000	3,500	$ 2,100
Capitalized internal-use software costs for works in process			$ 3,800

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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-Name Accounting Standards Codification
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- Definition

Amount of expense for amortization of capitalized computer software costs.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-Publisher FASB
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