Quarterly report pursuant to Section 13 or 15(d)

Employee Benefit Plan - Additional Information (Detail)

v3.8.0.1
Employee Benefit Plan - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Defined Contribution Plan Disclosure [Line Items]    
Defined contribution plan description The Company provides a 401(k) defined contribution plan (the Plan) for participation by all regular fulltime employees who have completed three months of service  
Percentage of matching contribution to plan 100.00%  
Percentage of salary for matching contribution per employee 3.00%  
Percentage of additional matching contribution to plan 50.00%  
Contributions to the plan by employer $ 49 $ 27
Minimum [Member]    
Defined Contribution Plan Disclosure [Line Items]    
Percentage of salary for additional matching contribution per employee 3.00%  
Maximum [Member]    
Defined Contribution Plan Disclosure [Line Items]    
Percentage of salary for additional matching contribution per employee 5.00%