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Technology Acquisition Agreement - Additional Information (Detail)	1 Months Ended		9 Months Ended
	May 31, 2014 USD ($)	Jun. 30, 2007 USD ($)	Sep. 30, 2020 USD ($) Milestone	Jun. 30, 2016 USD ($)
Technology Acquisition Agreement [Line Items]
Payment expensed as in-process research and development		$ 650,000
Mallinckrodt Plc [Member]
Technology Acquisition Agreement [Line Items]
Milestone payments contingent amount			$ 5,000,000
Number of milestone payments \| Milestone			1
Mallinckrodt Plc [Member] \| Gimoti [Member]
Technology Acquisition Agreement [Line Items]
Amount payable to Mallinckro dt				$ 5,000,000
Borrowing due date			Jun. 19, 2021
Research and development expense payable			$ 5,000,000
Mallinckrodt Plc [Member] \| Rights and Patents Acquired from Questcor Pharmaceuticals Inc [Member] \| Maximum [Member]
Technology Acquisition Agreement [Line Items]
Milestone payments contingent amount			$ 52,000,000
Development Target One [Member] \| Rights and Patents Acquired from Questcor Pharmaceuticals Inc [Member]
Technology Acquisition Agreement [Line Items]
Milestone payment	$ 500,000
Development targets description			Upon the initiation of the first patient dosing in the Company's Phase 3 clinical trial for Gimoti.
Development Target Four [Member] \| Mallinckrodt Plc [Member] \| Patented Technology [Member]
Technology Acquisition Agreement [Line Items]
Development targets description			Depend on Gimoti's commercial success and will only apply if Gimoti receives regulatory approval. In addition, the Company will be required to pay to Mallinckrodt a low single digit royalty on net sales of Gimoti.
Milestone payments contingent amount			$ 47,000,000
Expected expiration of patent right			2032