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Stock Based Compensation - Stock-Based Compensation Expense (Detail) (USD $)
In Thousands, unless otherwise specified |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
|
Sep. 30, 2013
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Sep. 30, 2012
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Sep. 30, 2013
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Sep. 30, 2012
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| Amortization of stock-based compensation: | ||||
| Stock-based compensation expense | $ 1,231 | $ 944 | $ 3,556 | $ 2,087 |
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Research and development [Member]
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| Amortization of stock-based compensation: | ||||
| Stock-based compensation expense | 622 | 471 | 1,818 | 1,082 |
|
General and administrative [Member]
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| Amortization of stock-based compensation: | ||||
| Stock-based compensation expense | $ 609 | $ 473 | $ 1,738 | $ 1,005 |