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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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-Name Accounting Standards Codification
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License Agreements and Acquired Product Rights - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Apr. 04, 2019
Indefinite-lived Intangible Assets [Line Items]
Milestone payment received			$ 200
Product Samples Purchased	$ 21,955	$ 14,021	38,944	$ 27,526
Percentage Of Sales Remaining For Sales Effected	65.00%
Milestone Payment Received Net Of Tax			160
Shiongi License And Supply Agreement [Member] \| Symproic License [Member]
Indefinite-lived Intangible Assets [Line Items]
Upfront Payment To Be Made					$ 20,000
Upfront Payment First Instalment To Be Made					20,000
Upfront Payment Instalment Henceforth To Be made					$ 10,000
Brief Of The License Covenants	Either party may terminate the License Agreement for cause if the other party materially breaches or defaults in the performance of its obligations. Unless earlier terminated, the License Agreement will continue in effect until the expiration of the Company's royalty obligations, as defined. Upon expiration of the License Agreement, all licenses granted to Company for Symproic in the Field and in the Territory survive and become fully-paid, royalty-free, perpetual and irrevocable.
Product Samples Purchased			400
Percentage Of Sales Retained By The Supplier	35.00%
Shiongi License And Supply Agreement [Member] \| Symproic License [Member] \| Acquisition Of Same Or Similar Class Of Assets [Member]
Indefinite-lived Intangible Assets [Line Items]
Tiered Royalty Payment As A Percentage Of Sales	100.00%
Shiongi License And Supply Agreement [Member] \| Symproic License [Member] \| Additional Royalty As A Percentage [Member]
Indefinite-lived Intangible Assets [Line Items]
Tiered Royalty Payment As A Percentage Of Sales	1.00%
TTY License and Supply Agreement [Member]
Indefinite-lived Intangible Assets [Line Items]
Royalties received			$ 300	$ 900
Royalty Agreement Terms [Member] \| Shiongi License And Supply Agreement [Member] \| Symproic License [Member] \| Maximum [Member]
Indefinite-lived Intangible Assets [Line Items]
Tiered Royalty Payment As A Percentage Of Sales	17.50%
Royalty Agreement Terms [Member] \| Shiongi License And Supply Agreement [Member] \| Symproic License [Member] \| Minimum [Member]
Indefinite-lived Intangible Assets [Line Items]
Tiered Royalty Payment As A Percentage Of Sales	8.50%