Leases - Additional Information (Detail) - USD ($) $ in Thousands		6 Months Ended
	Jan. 01, 2019	Jun. 30, 2019
Operating Leased Assets [Line Items]
Operating lease, right-of-use asset		$ 16,903
Operating lease, liability		$ 17,314
Accounting Standards Update 2016-02 [Member]
Operating Leased Assets [Line Items]
Operating lease, right-of-use asset	$ 18,200
Operating lease, liability	18,600
Deferred rent write off	$ 400
Lessee, operating lease, option to extend		Certain leases include options to extend the lease term for up to ten years
Accounting Standards Update 2016-02 [Member] | Minimum [Member]
Operating Leased Assets [Line Items]
Lessee, operating lease, term of contract		1 year
Accounting Standards Update 2016-02 [Member] | Maximum [Member]
Operating Leased Assets [Line Items]
Lessee, operating lease, term of contract		9 years