Stock-Based Compensation - Summarizes Information with Respect to Stock Options Outstanding (Detail) (USD $)	6 Months Ended
	Jun. 30, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Options, Shares	2,196,018
Outstanding Options, Weighted Average Remaining Contractual Term	9 years 7 months 10 days
Weighted Average Exercise Price	$ 2.65
Exercisable Options, Shares	241,960
Exercisable Options, Weighted Average Exercise Price	$ 2.27
Range of Exercise Prices - Range 1 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Options, Shares	1,293,720
Outstanding Options, Weighted Average Remaining Contractual Term	9 years 5 months 12 days
Weighted Average Exercise Price	$ 2.27
Exercisable Options, Shares	241,960
Exercisable Options, Weighted Average Exercise Price	$ 2.27
Range of Exercise Prices - Range 2 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Options, Shares	742,298
Outstanding Options, Weighted Average Remaining Contractual Term	9 years 9 months 29 days
Weighted Average Exercise Price	$ 3.04
Exercisable Options, Shares	0
Exercisable Options, Weighted Average Exercise Price	$ 0
Range of Exercise Prices - Range 3 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Options, Shares	160,000
Outstanding Options, Weighted Average Remaining Contractual Term	9 years 11 months 12 days
Weighted Average Exercise Price	$ 3.85
Exercisable Options, Shares	0
Exercisable Options, Weighted Average Exercise Price	$ 0