License Agreements and Acquired Product Rights - Additional Information (Detail) - Shiongi License And Supply Agreement - Symproic License - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Apr. 04, 2019
Indefinite-lived Intangible Assets [Line Items]
Upfront payment first installment to be made		$ 20
Upfront payment installment henceforth to be made		$ 10
Additional Royalty As A Percentage
Indefinite-lived Intangible Assets [Line Items]
Tiered royalty payment as a percentage of sales	1.00%
Royalty Agreement Terms \| Minimum
Indefinite-lived Intangible Assets [Line Items]
Tiered royalty payment as a percentage of sales	8.50%
Royalty Agreement Terms \| Maximum
Indefinite-lived Intangible Assets [Line Items]
Tiered royalty payment as a percentage of sales	17.50%

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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