Quarterly report pursuant to Section 13 or 15(d)

Property, Plant, and Equipment - Additional Information (Detail)

v3.8.0.1
Property, Plant, and Equipment - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Property Plant And Equipment [Abstract]    
Depreciation and amortization expenses $ 0.3 $ 0.3