Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($)
Accounting Policies [Abstract]
Write-down of inventory	$ 40
Minimum [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Intangible assets estimated useful lives	5 years
Maximum [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Intangible assets estimated useful lives	12 years