Acquisitions, Goodwill and Intangible Assets - Summary of Net Change in Carrying Value of Intangible Assets (Detail) - USD ($) $ in Thousands |
9 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2018 |
Dec. 31, 2017 |
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| Finite-Lived Intangible Assets, Net [Abstract] | ||
| Beginning balance | $ 0 | $ 0 |
| Additions from acquisition | 1,571 | 0 |
| Amortization | (118) | 0 |
| Ending balance | $ 1,453 | $ 0 |
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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