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Fair value assumptions, comparable yield to maturity.

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Significant accounting policies.

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Write offs of accounts receivables.

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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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Face (par) amount of the original debt instrument that was repurchased.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, after accumulated amortization, of debt discount.

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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

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Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Significant Accounting Policies - Additional Information (Detail)	1 Months Ended			3 Months Ended		12 Months Ended
	Jan. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Jan. 31, 2012	Mar. 31, 2017 USD ($) Segment	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Nov. 30, 2015 USD ($)	Dec. 31, 2012 USD ($)
Significant Accounting Policies [Line Items]
Sales discount percentage				2.00%
Sales discount term				30 days
Trade receivables, credit period				30 days
Accounts receivable written off				$ 0
Loss on change in fair value of derivative liabilities					$ 1,250,000
Number of operating segments \| Segment				1
Embedded Derivative Financial Instruments \| BioPharma Debt
Significant Accounting Policies [Line Items]
Maximum repayment of future revenue and receivables									$ 150,000,000
Fair value of embedded derivative liability		$ 5,900,000		$ 0	5,900,000	$ 0	$ 5,500,000
Loss on change in fair value of derivative liabilities				$ 0	$ 400,000
Embedded Derivative Financial Instruments \| BioPharma Debt \| Minimum
Significant Accounting Policies [Line Items]
Derivative liability fair value assumptions, term				2 years 1 month 6 days		2 years 4 months 24 days
Derivative liability fair value assumption, coupon rate				8.10%		8.10%
Derivative liability fair value assumptions, market yields				10.50%		11.90%
Embedded Derivative Financial Instruments \| BioPharma Debt \| Maximum
Significant Accounting Policies [Line Items]
Derivative liability fair value assumptions, term				4 years 8 months 12 days		5 years
Derivative liability fair value assumption, coupon rate				11.10%		11.10%
Derivative liability fair value assumptions, market yields				18.80%		18.40%
Top Three Customers \| Gross Product Sales \| Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage				95.00%	95.00%
Top Three Customers \| Accounts Receivable \| Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage				97.00%	95.00%
2012 Notes
Significant Accounting Policies [Line Items]
Aggregate principal amount of notes	$ 15,000,000
Aggregate principal amount redeemed	100,000
2017 Notes
Significant Accounting Policies [Line Items]
Aggregate principal amount of notes				$ 30,000,000
Convertible senior notes, discount				$ 1,200,000
Convertible Debt \| 2012 Notes
Significant Accounting Policies [Line Items]
Aggregate principal amount of notes						$ 15,107,000
Convertible senior notes, discount						$ 0
Note, expected term			24 months	24 months
Convertible senior notes, principal amount purchase	$ 15,000,000			$ 15,000,000				$ 16,200,000
Convertible senior notes, aggregate principal amount redeemed				100,000
Convertible senior notes, outstanding amount				0
Convertible Debt \| 2017 Notes
Significant Accounting Policies [Line Items]
Convertible senior notes, discount				1,200,000
Convertible Debt \| 2014 Notes
Significant Accounting Policies [Line Items]
Convertible senior notes, discount				27,900,000
Fair value of embedded derivative liability		2,800,000			$ 2,800,000		2,100,000
Loss on change in fair value of derivative liabilities		700,000			700,000
Convertible Debt \| 2014 Notes and 2015 Notes
Significant Accounting Policies [Line Items]
Loss on change in fair value of derivative liabilities				0
Convertible Debt \| 2015 Notes
Significant Accounting Policies [Line Items]
Convertible senior notes, discount				$ 3,800,000
Fair value of embedded derivative liability		$ 700,000			700,000		$ 600,000
Loss on change in fair value of derivative liabilities					100,000
ASU No. 2016-09 \| Scenario, Previously Reported
Significant Accounting Policies [Line Items]
Excess tax provision on stock-based awards					(100,000)
ASU No. 2016-09 \| Cumulative-effect adjustment
Significant Accounting Policies [Line Items]
Excess tax provision on stock-based awards					$ 100,000