Nature of Business and Summary of Significant Accounting Policies - Intangible Assets with Finite Useful Lives, Amortized Over Estimated Useful Lives (Detail)	12 Months Ended
	Dec. 31, 2019
Licenses
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	15 years
BELBUCA License and Distribution Rights
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	10 years
Symproic License
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	12 years
U.S. Product Rights | Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	8 years
U.S. Product Rights | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	12 years
EU Product Rights | Minimum
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	7 years
EU Product Rights | Maximum
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives	11 years