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Debt investment maturity date description.

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No definition available.

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Debt investment maximum maturity period.

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Upfront and Milestone Payments Received Under License Agreement

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The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a)

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Subparagraph (SX 210.5-02.22(a)(1))

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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-Subparagraph (SX 210.5-02.22(a)(2))

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

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-Name Regulation S-X (SX)

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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), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Subparagraph (SX 210.5-02.22)

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-Section 02

-Paragraph 22

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Cash and Investments in Marketable Securities - Additional Information (Detail) (USD $)	3 Months Ended		0 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Dec. 31, 2014
Cash and Investments in Marketable Securities [Line Items]
Maximum maturity term for debt securities investment	Two years or less
Weighted average maturity term for debt securities investment	One year or less
Available-for-sale securities, sold	$ 5,200,000	$ 0.0
Restricted cash	25,000,000		25,000,000	25,000,000
Level 1 to level 2 transfers	0	0	0
Level 2 to level 1 transfers	0	0	0
Senior secured notes, carrying amount	125,000,000us-gaap_SeniorLongTermNotes		125,000,000us-gaap_SeniorLongTermNotes	125,000,000us-gaap_SeniorLongTermNotes
AstraZeneca AB [Member] \| United States [Member]
Cash and Investments in Marketable Securities [Line Items]
Received upfront and milestone payments			100,000,000
12% Senior Secured Notes Due July 2017 [Member]
Cash and Investments in Marketable Securities [Line Items]
Restricted cash	25,000,000		25,000,000
Senior secured notes, interest rate	12.00%		12.00%
Senior secured notes, maturity date	Jul. 15, 2017
12% Senior Secured Notes Due July 2017 [Member] \| Level 3 [Member]
Cash and Investments in Marketable Securities [Line Items]
Senior secured notes, interest rate	12.00%		12.00%
Senior secured notes, maturity date	Jul. 15, 2017
Senior secured notes, carrying amount	$ 125,000,000		$ 125,000,000