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Significant Accounting Policies - Additional Information (Detail)	9 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($) Segment Customer	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2012 USD ($)
Significant Accounting Policies [Line Items]
Trade receivables, credit period	30 days
Maturities period	24 months
Unrealized gain on held-to-maturity securities	$ 900,000
Number of operating segments | Segment	1
ASU No. 2018-18
Significant Accounting Policies [Line Items]
Change in accounting principle, accounting standards update, adopted [true false]	true
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2020
Change in accounting principle, accounting standards update, immaterial effect [true false]	true
ASU No. 2018-13
Significant Accounting Policies [Line Items]
Change in accounting principle, accounting standards update, adopted [true false]	true
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2020
Change in accounting principle, accounting standards update, immaterial effect [true false]	true
ASU No. 2016-13
Significant Accounting Policies [Line Items]
Change in accounting principle, accounting standards update, adopted [true false]	true
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2020
Change in accounting principle, accounting standards update, immaterial effect [true false]	true
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%		6.00%
Derivative liability fair value assumptions, market yields	5.40%		5.20%
Embedded Derivative Financial Instruments | BioPharma Debt | Maximum
Significant Accounting Policies [Line Items]
Derivative liability fair value assumption, coupon rate	11.50%		11.50%
Derivative liability fair value assumptions, market yields	16.40%		16.80%
Embedded Derivative Financial Instruments | BioPharma Debt | Measurement Input, Expected Term | Minimum
Significant Accounting Policies [Line Items]
Derivative liability fair value assumptions, term	1 year 2 months 12 days		1 year 10 months 24 days
Embedded Derivative Financial Instruments | BioPharma Debt | Measurement Input, Expected Term | Maximum
Significant Accounting Policies [Line Items]
Derivative liability fair value assumptions, term	6 years 6 months		7 years 3 months 18 days
Short Term Investments
Significant Accounting Policies [Line Items]
Maturities period	12 months
Long Term Investments
Significant Accounting Policies [Line Items]
Maturities period	12 months
Money Market Instruments
Significant Accounting Policies [Line Items]
Maturities period	90 days
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	25.00%	25.00%
Customer A | Accounts Receivable | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	37.00%	42.00%
Customer B | Gross Product Sales | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	37.00%	36.00%
Customer B | Accounts Receivable | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	32.00%	23.00%
Customer C | Gross Product Sales | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	30.00%	29.00%
Customer C | Accounts Receivable | Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage	25.00%	28.00%

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