Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 134,554	$ 159,226
Prepaid expenses and other current assets	5,689	5,488
Total current assets	140,243us-gaap_AssetsCurrent	164,714us-gaap_AssetsCurrent
In-process research and development	58,200	58,200
Fixed assets, net	7,292us-gaap_PropertyPlantAndEquipmentNet	7,534us-gaap_PropertyPlantAndEquipmentNet
Other assets	417us-gaap_OtherAssets	416us-gaap_OtherAssets
Total assets	206,152us-gaap_Assets	230,864us-gaap_Assets
Current liabilities:
Accounts payable	7,860us-gaap_AccountsPayableCurrent	9,249us-gaap_AccountsPayableCurrent
Accrued expenses	5,976us-gaap_AccruedLiabilitiesCurrent	5,321us-gaap_AccruedLiabilitiesCurrent
Accrued compensation	1,584	4,317
Other current liabilities	716us-gaap_OtherLiabilitiesCurrent	743us-gaap_OtherLiabilitiesCurrent
Current portion of long term debt	24,989us-gaap_LongTermDebtCurrent
Total current liabilities	41,125us-gaap_LiabilitiesCurrent	19,630us-gaap_LiabilitiesCurrent
Long-term liabilities:
Other long-term liabilities	162us-gaap_OtherLiabilitiesNoncurrent	141us-gaap_OtherLiabilitiesNoncurrent
Debt, long-term		24,856us-gaap_LongTermDebtNoncurrent
Total liabilities	41,287us-gaap_Liabilities	44,627us-gaap_Liabilities
Shareholders' equity:
Common stock, $0.01 par value; 500,000,000 authorized shares, 50,001,770 and 49,806,131 issued and outstanding shares at March 31, 2015 and December 31, 2014, respectively	500us-gaap_CommonStockValue	498us-gaap_CommonStockValue
Additional paid-in capital	662,514us-gaap_AdditionalPaidInCapital	656,519us-gaap_AdditionalPaidInCapital
Accumulated deficit	(498,149)	(470,780)
Total shareholders' equity	164,865us-gaap_StockholdersEquity	186,237us-gaap_StockholdersEquity
Total liabilities and shareholders' equity	$ 206,152	$ 230,864

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Subparagraph a

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(a))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682