Consolidated Statements of Comprehensive Loss (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues
Product sales, net	$ 33us-gaap_SalesRevenueGoodsNet
Royalty revenue	3,025us-gaap_RoyaltyRevenue	2,562us-gaap_RoyaltyRevenue	3,317us-gaap_RoyaltyRevenue
Collaborative and other research and development	10,550	14,769	22,976
Total revenues	13,608us-gaap_SalesRevenueNet	17,331us-gaap_SalesRevenueNet	26,293us-gaap_SalesRevenueNet
Expenses
Cost of products sold	1us-gaap_CostOfGoodsSold
Research and development	51,796us-gaap_ResearchAndDevelopmentExpense	41,943us-gaap_ResearchAndDevelopmentExpense	49,160us-gaap_ResearchAndDevelopmentExpense
General and administrative	7,461us-gaap_GeneralAndAdministrativeExpense	6,007us-gaap_GeneralAndAdministrativeExpense	9,130us-gaap_GeneralAndAdministrativeExpense
Royalty	121us-gaap_RoyaltyExpense	98us-gaap_RoyaltyExpense	132us-gaap_RoyaltyExpense
Restructuring		(97)us-gaap_RestructuringCharges	1,759us-gaap_RestructuringCharges
Total operating expenses	59,379us-gaap_CostsAndExpenses	48,048us-gaap_CostsAndExpenses	60,181us-gaap_CostsAndExpenses
Loss from operations	(45,771)us-gaap_OperatingIncomeLoss	(30,717)us-gaap_OperatingIncomeLoss	(33,888)us-gaap_OperatingIncomeLoss
Interest and other income	93us-gaap_InterestAndOtherIncome	93us-gaap_InterestAndOtherIncome	222us-gaap_InterestAndOtherIncome
Interest expense	(4,998)us-gaap_InterestExpense	(4,778)us-gaap_InterestExpense	(4,666)us-gaap_InterestExpense
Gain (loss) on foreign currency derivative	5,487	5,294	(749)
Net loss	(45,189)us-gaap_NetIncomeLoss	(30,108)us-gaap_NetIncomeLoss	(39,081)us-gaap_NetIncomeLoss
Basic and diluted net loss per common share (in Dollars per share)	$ (0.68)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.55)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.79)us-gaap_EarningsPerShareBasicAndDiluted
Weighted average shares outstanding (in Shares)	66,773	55,216	49,474
Unrealized loss on available for sale investments	(134)	(23)	(13)
Comprehensive loss	$ (45,323)us-gaap_ComprehensiveIncomeNetOfTax	$ (30,131)us-gaap_ComprehensiveIncomeNetOfTax	$ (39,094)us-gaap_ComprehensiveIncomeNetOfTax

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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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