| **Accounts Payable and Accrued Expenses**            | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
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| **Accounts Payable and Accrued Expenses [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Accounts Payable and Accrued Expenses                | 6.  Accounts Payable and Accrued Expenses  September 30,2012 December 31,2011Accrued payroll and related costs $1,845 $3,149Accrued consulting and clinical trial costs  1,964  1,637Restructuring costs  1,886  731Legal and professional fees  593  371Accounts payable  125  309Other  73  134Total $6,486 $6,331Accounts payable and accrued expenses increased as of September 30, 2012, compared to year end, primarily due to higher restructuring costs and legal and professional fees, partially offset by decrease due to the payment of 2011 accrued bonuses in the first quarter of 2012.  |

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| - Definition
The entire disclosure for accounts payable and accrued liabilities at the end of the reporting period.
+ References
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 5Reference 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),20,24) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 24 -Article 5
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| - Details**Name:**us-gaap_PayablesAndAccrualsAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |