Net Loss Per Share - Schedule of Securities Excluded from Calculation of Net (Loss) per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive excluded from computation of earnings per share amount	15,065,342	14,560,119	4,486,160
Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive excluded from computation of earnings per share amount	40,000	40,000	40,000
Common Stock Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive excluded from computation of earnings per share amount	9,357	120,702	160,816
2018 Convertible Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive excluded from computation of earnings per share amount	11,401,284	11,401,284	343,600
Common Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive excluded from computation of earnings per share amount	1,441,086	2,173,916	2,934,625
Restricted Stock Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive excluded from computation of earnings per share amount	2,173,615	824,217	1,007,119