Summary of Significant Accounting Policies - Basic and Diluted Net Loss Per Share (Detail) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	144	155
Options to purchase common stock
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	6	91
Restricted stock units not yet vested and released
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	106	0
Warrants to purchase common stock
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	32	64