Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($) Customer	Jun. 30, 2016 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Other non-cash adjustments, net | $	$ 210	$ 226
Percentage of insurance coverage gap allocated for prescription drugs under Medicare Part D	50.00%
Purchases of property, plant and equipment and the related current liability | $	$ 300	$ 0
Customer Concentration Risk | Sales Revenue, Net
Summary Of Significant Accounting Policies [Line Items]
Concentration Risk, Percentage	87.00%
Number of major customers that each accounted for more than 10% of total revenues | Customer	5
Credit Concentration Risk | Accounts Receivable
Summary Of Significant Accounting Policies [Line Items]
Concentration Risk, Percentage	77.00%
Number of major customers that each accounted for more than 10% of total accounts receivable | Customer	4