Annual report pursuant to Section 13 and 15(d)

Amortizable Intangible Assets - Additional Information (Detail)

v3.19.1
Amortizable Intangible Assets - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]    
Amortization of intangible assets $ 6.2 $ 4.6