Summary of Significant Accounting Policies - Basic and Diluted Net Loss Per Share (Detail) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 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	106	1,786	106	1,786
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	2	1,786	2	1,786
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	104	0	104	0