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Lease Exit Liability (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014 | Jul. 16, 2008
Restructuring Cost and Reserve [Line Items] |  |  |  |  |
Lease expiration year |  |  | 2018 |  |
Restructuring Costs [Abstract] |  |  |  |  |
Potential future payment under purchase agreement |  |  |  |  | $ 5,000
Incremental in-process research and development expense | $ 0 | $ 0 | $ 0 | $ 0 |
Minimum [Member] |  |  |  |  |
Restructuring Costs [Abstract] |  |  |  |  |
Potential payment under license of product |  |  |  |  | 8,000
Maximum [Member] |  |  |  |  |
Restructuring Costs [Abstract] |  |  |  |  |
Potential payment under license of product |  |  |  |  | $ 12,000
Contract Termination [Member] |  |  |  |  |
Restructuring Costs [Abstract] |  |  |  |  |
Accrual beginning balance |  |  | 8,006 |  |
Principal payments |  |  | (2,833) |  |
Accrual ending balance | $ 5,173 |  | $ 5,173 |  |

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