Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Consolidated Statements of Operations
Royalty revenue from a related party, net of intangible assets amortization of $743 in 2013 and $0 in 2012 and 2011	$ 1,202	$ 0	$ 0
Net revenue from collaborative arrangements (including amounts from a related party of $3,330 in 2013, $5,613 in 2012, and $9,658 in 2011)	3,556	135,758	24,512
Total net revenue	4,758	135,758	24,512
Operating expenses:
Research and development	125,181	117,898	103,568
Selling, general and administrative	48,440	30,859	30,681
Total operating expenses	173,621	148,757	134,249
Loss from operations	(168,863)	(12,999)	(109,737)
Other income (expense), net	6,732	0	0
Interest income	778	460	415
Interest expense	(9,348)	(6,003)	(6,022)
Net loss	$ (170,701)	$ (18,542)	$ (115,344)
Basic and diluted net loss per share (in dollars per share)	$ (1.67)	$ (0.20)	$ (1.41)
Shares used to compute basic and diluted net loss per share (in shares)	102,425	90,909	82,051

Revenue earned under collaborative arrangements from upfront payments and contingent payments.

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Represents revenue net of amortization expense from related intangible assets earned during the period from the leasing or otherwise lending to a related party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. An example of property from which royalties may be derived includes patents.

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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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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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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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