Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Stock Option and Incentive Plans - Additional Information (Detail)

v3.10.0.1

Stock Option and Incentive Plans - Additional Information (Detail) - USD ($)			3 Months Ended		9 Months Ended
	Dec. 31, 2015	Feb. 26, 2013	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Jul. 28, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved pursuant to the plan			38,513,380		38,513,380		42,470,254
Weighted average grant date fair value of options					$ 1.45	$ 1.73
Unrecognized compensation cost related to unvested stock options			$ 2,700,000		$ 2,700,000
Weighted average period of unvested stock options					2 years 8 months 4 days
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense recognized			$ 383,158	$ 1,236,972	$ 359,376	$ 1,087,179
Amended and Restated 2008 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved pursuant to the plan		1,571,428
Termination of service, Period		2 years
2008 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Termination of service, Period		10 years
2014 Omnibus Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved pursuant to the plan								571,429
Number of additional shares increases of common stock reserved pursuant to the plan					6,520,477
2014 Omnibus Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual increase of plan, percentage of common stock shares outstanding	4.00%

- Definition

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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Aggregate number of common shares reserved for future issuance.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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- Definition

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

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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