Quarterly report pursuant to Section 13 or 15(d)

Intangible Assets, Net - Additional Information (Detail)

v3.10.0.1
Intangible Assets, Net - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Dec. 31, 2017
Intangible Assets Net Excluding Goodwill [Abstract]          
Amortization expenses of intangible assets $ 420 $ 456 $ 1,265 $ 1,369 $ 1,826