Annual report pursuant to Section 13 and 15(d)

Income Taxes - Reconciliation - (Details)

v3.6.0.2
Income Taxes - Reconciliation - (Details)
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Reconciliation of statutory income tax rate to effective tax rate:      
Federal income tax computed at federal statutory tax rate (as a percent) 34.00% 34.00% 34.00%
State income tax, net of federal benefit (as a percent) 4.79% 4.70% 4.86%
Permanent items (as a percent) (2.83%) (3.33%) (1.94%)
Federal and state research and development credits (as a percent) 2.93% 2.66% 4.73%
Other (as a percent) (0.08%) 0.12%  
Change in valuation allowance (as a percent) (38.81%) (38.15%) (41.65%)
Effective tax rate (as a percent) 0.00% 0.00% 0.00%