Leases - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Jan. 01, 2019
Leases [Abstract]
Operating lease right-of-use assets	$ 38,187	$ 38,187	$ 10,400
Operating lease liability	39,487	39,487	$ 10,400
Operating lease cost	5,600	7,900
Operating lease liability current	$ 17,166	$ 17,166
Weighted average remaining lease term	3 years 6 months	3 years 6 months
Weighted average discount cate	5.60%	5.60%