Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	9 Months Ended
May 31, 2018	Sep. 30, 2018
Goodwill [Line Items]
Amortization of intangible asset		$ 3.0
Goodwill		$ 68.5
Domain Names [Member]
Goodwill [Line Items]
Amortization period		15 years
Purchase of domain names	$ 6.3
Customer Backlog [Member]
Goodwill [Line Items]
Amortization period		12 months
Trade Names and Trademarks [Member]
Goodwill [Line Items]
Amortization period		12 months

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

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

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-Publisher FASB
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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.

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- Definition

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.

+ References

No definition available.

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