Stockholders' Equity and Stock-Based Compensation - Summary of Stock-Based Compensation Expense by Award Type (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 2,804	$ 1,012	$ 7,701	$ 7,699
Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	994	$ 1,012	3,130	2,285
Unvested Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation				61
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	1,273		2,948
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 537		$ 1,623
Employee Sale of Securities to Investors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation				$ 5,353