v3.10.0.1
Income Taxes - Schedule of Reconciliation of Statutory Federal Income Tax Rate to Effective Tax Rate (Details)
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Income Tax Disclosure [Abstract]      
U.S. federal income tax at statutory rate 21.00% 34.00% 34.00%
U.S. state and local income taxes (1.30%) (0.20%) (0.10%)
Change in valuation allowance (1039.40%) 19.00% (36.90%)
Federal research and development tax credit 166.20% 5.20% 4.80%
Convertible preferred stock warrants   (21.70%) 0.70%
Stock-based compensation 859.40% 1.20% (2.50%)
Meals and Entertainment (6.60%) (1.10%) (0.20%)
Permanent items (1.10%)    
Foreign rate differential (1.50%) 0.20%  
Tax rate change 2.40% (36.40%)  
Provision to return trueup 5.90%    
Other 0.10% (0.70%) (0.20%)
Effective tax rate 5.10% (0.50%) (0.40%)