Summary of Significant Accounting Policies - Schedule of Anti-dilutive Securities Excluded from Diluted Loss Per Share (Detail) - shares	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted loss per share	3,095,132	3,261,023
Stock options [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted loss per share	1,361,567	1,266,087
Warrants [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted loss per share	1,733,565	1,994,936