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Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019 USD ($) Segment Customer	Dec. 31, 2018 USD ($)	Dec. 31, 2017	Dec. 31, 2012 USD ($)
Significant Accounting Policies [Line Items]
Trade receivables, credit period	30 days
U.S. federal corporate tax rate	21.00%	21.00%	34.00%
Number of operating segments | Segment	1
Minimum
Significant Accounting Policies [Line Items]
Trade receivables, credit period	30 days
Maximum
Significant Accounting Policies [Line Items]
Trade receivables, credit period	60 days
Embedded Derivative Financial Instruments | BioPharma Debt
Significant Accounting Policies [Line Items]
Maximum repayment of future revenue and receivables				$ 150,000,000.0
Fair value of embedded derivative liability	$ 0	$ 0
Gain (loss) on change in fair value of derivative liabilities	$ 0	$ 0
Embedded Derivative Financial Instruments | BioPharma Debt | Minimum
Significant Accounting Policies [Line Items]
Derivative liability fair value assumption, coupon rate	6.00%	5.40%
Derivative liability fair value assumptions, market yields	5.20%	6.70%
Embedded Derivative Financial Instruments | BioPharma Debt | Maximum
Significant Accounting Policies [Line Items]
Derivative liability fair value assumption, coupon rate	11.50%	10.80%
Derivative liability fair value assumptions, market yields	16.80%	15.80%
Embedded Derivative Financial Instruments | BioPharma Debt | Measurement Input, Expected Term | Minimum
Significant Accounting Policies [Line Items]
Derivative liability fair value assumptions, term	1 year 10 months 24 days	1 year 3 months 18 days
Embedded Derivative Financial Instruments | BioPharma Debt | Measurement Input, Expected Term | Maximum
Significant Accounting Policies [Line Items]
Derivative liability fair value assumptions, term	7 years 3 months 18 days	4 years
Gross Product Sales | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Number of customers | Customer	3
Customer A | Gross Product Sales | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	36.00%	31.00%
Customer A | Accounts Receivable | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	35.00%	26.00%
Customer B | Gross Product Sales | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	29.00%	30.00%
Customer B | Accounts Receivable | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	20.00%	24.00%
Customer C | Gross Product Sales | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	25.00%	27.00%
Customer C | Accounts Receivable | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	37.00%	39.00%
2017 Notes
Significant Accounting Policies [Line Items]
Aggregate principal amount of notes	$ 30,000,000.0
Convertible senior notes, discount	$ 1,200,000

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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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