Annual report pursuant to Section 13 and 15(d)

Commitments and Contingencies - Additional Information (Detail)

v3.10.0.1
Commitments and Contingencies - Additional Information (Detail)
12 Months Ended
Apr. 16, 2018
USD ($)
ft²
Nov. 08, 2013
ft²
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Loss Contingencies [Line Items]          
Rent expenses     $ 300,000 $ 300,000 $ 300,000
Lease expiration date Jan. 15, 2024        
Lease term, option to renew period 5 years        
Area of office space to be expanded | ft² 17,698        
Accretion of tenant improvement allowance $ 2,300,000   263,000    
Indemnification liabilities     0 $ 0  
Accrued in the consolidated balance sheets related to indemnification obligations     $ 0    
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