Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies - Additional Information (Detail)

v3.10.0.1
Commitments and Contingencies - Additional Information (Detail)
$ in Thousands
3 Months Ended 6 Months Ended
Apr. 16, 2018
USD ($)
Nov. 08, 2013
ft²
Jun. 30, 2018
USD ($)
Jun. 30, 2017
USD ($)
Jun. 30, 2018
USD ($)
Jun. 30, 2017
USD ($)
Loss Contingencies [Line Items]            
Lease expiration date Jan. 15, 2024          
Lease term, option to renew period 5 years          
Accretion of tenant improvement allowance $ 2,100       $ 61  
Rent expenses     $ 100 $ 100 $ 300 $ 300
Lease Facility [Member]            
Loss Contingencies [Line Items]            
Area of office space | ft²   8,894        
Lease start date   Jan. 16, 2014        
Lease expiration date   Jan. 15, 2019