Annual report pursuant to Section 13 and 15(d)

Commitments and Contingencies - Additional Information Operating Leases (Detail)

v3.10.0.1
Commitments and Contingencies - Additional Information Operating Leases (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]      
Deferred rent $ 5.6 $ 4.8  
Rental expense $ 27.7 $ 25.6 $ 23.4