Annual report pursuant to Section 13 and 15(d)

Cover
- Cover Page
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)

v3.20.1

Stock Option and Incentive Plans - Additional Information (Detail) - USD ($)			12 Months Ended
	Dec. 31, 2015	Feb. 26, 2013	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jul. 28, 2014	Apr. 29, 2014	Feb. 24, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved pursuant to the plan			4,351,873	4,125,267
Number of common stock shares outstanding			1,216,338	718,796
Number of common stock available for grant			65,076
Weighted average grant date fair value of options			$ 4.30	$ 1.47	$ 1.62
Unrecognized compensation cost related to unvested stock options			$ 2,547,923
Weighted average period of unvested stock options			2 years 5 months 23 days
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense recognized			$ 1,446,549	$ 1,555,523	$ 1,623,128
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		157,143
Termination of service, Period		2 years
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							235,714	185,714
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						57,143
Number of additional shares increases of common stock reserved pursuant to the plan			969,685
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%

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