Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Sale Leaseback Transaction [Line Items]
Accrued in other current liabilities	$ 9,061		$ 9,061		$ 4,999
Company had royalty and license expenses relating to those agreements	200	$ 600	500	$ 100
Claims and litigation [Member]
Sale Leaseback Transaction [Line Items]
Accrued in other current liabilities	0		0
Research and Development Agreements [Member]
Sale Leaseback Transaction [Line Items]
Current commitments	$ 400		$ 400		$ 2,300