Goodwill and Intangible Assets, Net - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill	$ 51,889,000		$ 51,889,000		$ 51,889,000
Goodwill impairment amount			$ 0		$ 0
Weighted average remaining useful life			5 years
Amortization of intangible assets	$ 400,000	$ 400,000	$ 800,000	$ 800,000