Annual report pursuant to Section 13 and 15(d)

Income Taxes - Schedule of Activity Related to Unrecognized Tax Benefits (Detail)

v3.8.0.1
Income Taxes - Schedule of Activity Related to Unrecognized Tax Benefits (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Income Tax Disclosure [Abstract]    
Gross unrecognized tax benefits at January 1, $ 0 $ 0
Gross increases (decreases) related to acquisitions 1,064 0
Gross increases (decreases) related to current year tax positions 79 0
Gross unrecognized tax benefits at December 31, $ 1,143 $ 0