Net Sales by Product (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Sales Information [Line Items]
Net product sales	$ 30,306	$ 14,156	$ 79,752	$ 37,611
BELBUCA
Sales Information [Line Items]
Net product sales	26,514	12,358	69,277	30,128
Symproic
Sales Information [Line Items]
Net product sales	2,172	0	5,348	0
BUNAVAIL
Sales Information [Line Items]
Net product sales	937	1,405	2,813	4,239
Product sales
Sales Information [Line Items]
Net product sales	$ 29,623	$ 13,763	$ 77,438	$ 34,367

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration