Annual report pursuant to Section 13 and 15(d)

401(k) Plan - Additional Information (Detail)

v3.10.0.1
401(k) Plan - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Defined Contribution Pension And Other Postretirement Plans Disclosure [Abstract]      
Employees contribution to qualified savings plan $ 750 $ 0 $ 0