Stock Option Plans - Summary of Option Activity for Employees and Non-Employees (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Exercised		(75,000)
Vested Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Beginning Balance	1,036,185	1,115,006
Number of Options, Exercised	(200,000)	(312,293)
Number of Options, Ending Balance	1,041,680	1,036,185	1,115,006
Number of Options, Vested	(215,495)	(324,018)
Number of Options, Forfeited	(10,000)	(90,546)
Weighted Averaged Exercise Price, Beginning Balance	$ 1.11	$ 0.97
Weighted Averaged Exercise Price, Exercised	1.00	0.93
Weighted Averaged Exercise Price, Forfeited or expired	1.00	1.30
Weighted Averaged Exercise Price, Ending Balance	1.29	1.11	$ 0.97
Weighted Averaged Exercise Price, Vested	$ 1.92	$ 1.45
Nonvested Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Beginning Balance	435,945	369,493
Number of Options, Granted	157,306	390,470
Number of Options, Ending Balance	377,756	435,945	369,493
Number of Options, Vested	(215,495)	(324,018)
Weighted Averaged Exercise Price, Beginning Balance	$ 1.87	$ 1.22
Weighted Averaged Exercise Price, Granted	3.01	2.18
Weighted Averaged Exercise Price, Ending Balance	2.32	1.87	$ 1.22
Weighted Averaged Exercise Price, Vested	$ 1.92	$ 1.45
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Beginning Balance	1,472,130	1,484,499
Number of Options, Granted	157,306	390,470
Number of Options, Exercised	(200,000)	(312,293)
Number of Options, Forfeited or expired	(10,000)	(90,546)
Number of Options, Ending Balance	1,419,436	1,472,130	1,484,499
Number of Options, Exercisable, Ending Balance	1,041,680	1,036,185
Weighted Averaged Exercise Price, Beginning Balance	$ 0.79	$ 1.03
Weighted Averaged Exercise Price, Granted	3.01	2.25
Weighted Averaged Exercise Price, Exercised	1.00	0.93
Weighted Averaged Exercise Price, Forfeited or expired	1.00	1.30
Weighted Averaged Exercise Price, Ending Balance	1.56	0.79	$ 1.03
Weighted Averaged Exercise Price, Exercisable, Ending Balance	$ 1.29	$ 1.10
Weighted Average Remaining Contractual Life (Years), Outstanding	2 years 9 months 11 days	3 years 3 months 11 days	2 years 10 months 17 days
Weighted Average Remaining Contractual Life (Years), Granted	4 years 2 months 5 days	4 years 10 months 13 days
Weighted Average Remaining Contractual Life (Years), Exercisable	2 years 4 months 28 days	2 years 9 months
Aggregate Intrinsic Options Value, Beginning Balance	$ 1,430,231
Aggregate Intrinsic Options Value, Exercisable, Beginning Balance	1,244,074
Aggregate Intrinsic Options Value, Ending Balance	1,220,338	$ 1,430,231
Aggregate Intrinsic Options Value, Exercisable, Ending Balance	$ 1,135,819	$ 1,244,074
Weighted Averaged Exercise Price, Exercisable, Beginning Balance	$ 1.10
Number of Options, Exercisable, Beginning Balance	1,036,185
Option Activity for Non-Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Beginning Balance	16,666	173,332
Number of Options, Granted	8,333
Number of Options, Exercised	(16,666)	(151,666)
Number of Options, Forfeited or expired		(5,000)
Number of Options, Ending Balance	8,333	16,666	173,332
Number of Options, Exercisable, Ending Balance	2,777	16,666	173,332
Weighted Averaged Exercise Price, Beginning Balance	$ 1.27	$ 0.48
Weighted Averaged Exercise Price, Granted	2.70
Weighted Averaged Exercise Price, Exercised		0.38
Weighted Averaged Exercise Price, Ending Balance	2.70	1.27	$ 0.48
Weighted Averaged Exercise Price, Exercisable, Ending Balance	$ 2.70	$ 1.27	$ 0.48
Weighted Average Remaining Contractual Life (Years), Outstanding	4 years 9 months 29 days	7 months 13 days	7 months 2 days
Weighted Average Remaining Contractual Life (Years), Granted	4 years 9 months 29 days
Weighted Average Remaining Contractual Life (Years), Exercisable	4 years 9 months 29 days	7 months 13 days	7 months 2 days
Aggregate Intrinsic Options Value, Beginning Balance	$ 17,166	$ 210,833
Aggregate Intrinsic Options Value, Exercisable, Beginning Balance	17,166	210,833
Aggregate Intrinsic Options Value, Ending Balance		17,166	$ 210,833
Aggregate Intrinsic Options Value, Exercisable, Ending Balance		$ 17,166	$ 210,833
Aggregate Intrinsic Options Value, Granted	$ 22,499
Weighted Averaged Exercise Price, Exercisable, Beginning Balance	$ 1.27	$ 0.48
Weighted Averaged Exercise Price, Forfeited		$ 1.15
Number of Options, Exercisable, Beginning Balance	16,666	173,332
Option Activity for Non-Employees [Member] | Vested Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Beginning Balance	16,666	173,332
Number of Options, Exercised	(166,666)	(151,666)
Number of Options, Forfeited or expired		(5,000)
Number of Options, Ending Balance	2,777	16,666	173,332
Number of Options, Vested	(5,556)
Weighted Averaged Exercise Price, Beginning Balance	$ 1.27	$ 0.48
Weighted Averaged Exercise Price, Exercised	1.27	0.38
Weighted Averaged Exercise Price, Ending Balance	2.70	1.27	$ 0.48
Weighted Averaged Exercise Price, Vested	$ 2.70
Weighted Averaged Exercise Price, Forfeited		$ 1.15
Option Activity for Non-Employees [Member] | Nonvested Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Granted	8,333	0
Number of Options, Ending Balance	5,556
Number of Options, Vested	(2,777)
Weighted Averaged Exercise Price, Granted	$ 2.70
Weighted Averaged Exercise Price, Ending Balance	2.70
Weighted Averaged Exercise Price, Vested	$ 3.70