Summary of Significant Accounting Policies - Basic and Diluted Net Loss Per Share (Detail) - shares shares in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2016	Jun. 30, 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	110	521		110	297
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	3	521		3	297
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	107	0		107	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	0	0	0	0