Segment Reporting - Summary of Net Sales by Product (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Sales Information [Line Items]
Net product sales	$ 7,886	$ 2,110	$ 15,680	$ 4,212
Belbuca [Member]
Sales Information [Line Items]
Net product sales	6,563		11,117		$ 0
BUNAVAIL [Member]
Sales Information [Line Items]
Net product sales	$ 1,323	$ 2,110	$ 4,563	$ 4,212