The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

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No definition available.

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Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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Stock option issuance period.

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Stock-Based Awards - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Jun. 20, 2016	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Stock option issuance period				10 years
Option vested period				1 year
Option issued period				Stock options may be issued for terms of ten years
Shares of common stock authorized to issue under equity award plan	10,000,000
Description of new equity award plan				On June 20, 2016, the Company's stockholders approved a new equity award plan under which the Company can issue up to 10,000,000 shares of common stock (less one share for every share granted under prior plans since March 31, 2016 and inclusive of shares available under the prior plans as of March 31, 2016) in the form of stock options and other stock-based awards.
Stock-based compensation expense		$ 3,240	$ 3,607	$ 10,078	$ 10,558