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Stock Based Compensation - Stock-Based Compensation Expense (Detail) (USD $)
In Thousands, unless otherwise specified |
3 Months Ended | |
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Mar. 31, 2013
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Mar. 31, 2012
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| Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | ||
| Stock-based compensation expense | $ 1,053 | $ 398 |
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Research and development [Member]
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| Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | ||
| Stock-based compensation expense | 534 | 240 |
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General and administrative [Member]
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| Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | ||
| Stock-based compensation expense | $ 519 | $ 158 |
| X | ||||||||||
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- Definition
Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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