Condensed Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Consolidated Statements of Operations
Collaborative arrangements revenue	$ 28,932us-gaap_Revenues	$ 14,605us-gaap_Revenues
Cost and expenses:
Cost of revenue	12us-gaap_CostOfRevenue	1,924us-gaap_CostOfRevenue
Research and development	26,641us-gaap_ResearchAndDevelopmentExpense	27,144us-gaap_ResearchAndDevelopmentExpense
Selling, general and administrative	30,346	29,924
Total cost and expenses	56,999us-gaap_CostsAndExpenses	58,992us-gaap_CostsAndExpenses
Loss from operations	(28,067)us-gaap_OperatingIncomeLoss	(44,387)us-gaap_OperatingIncomeLoss
Other (expense) income:
Interest expense	(5,220)us-gaap_InterestExpense	(5,283)us-gaap_InterestExpense
Interest and investment income	65us-gaap_InvestmentIncomeNet	44us-gaap_InvestmentIncomeNet
Other expense, net	(5,155)us-gaap_NonoperatingIncomeExpense	(5,239)us-gaap_NonoperatingIncomeExpense
Net loss	$ (33,222)	$ (49,626)
Net loss per share - basic and diluted	$ (0.24)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.38)us-gaap_EarningsPerShareBasicAndDiluted
Weighted average number of common shares used in net loss per share - basic and diluted:	141,278	129,745

The aggregate cost of goods produced and sold and services rendered during the reporting period.

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Total costs of sales and operating expenses for the period.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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The net result for the period of deducting operating expenses from operating revenues.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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