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Summary of Significant Accounting Policies - Estimated Useful Lives (Detail) | 9 Months Ended
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Sep. 30, 2013
Computer Equipment [Member] |
Depreciation Amortization Impairment [Line Items] |
Estimated Useful Lives | 3 years
Software [Member] |
Depreciation Amortization Impairment [Line Items] |
Estimated Useful Lives | 3 years
Furniture [Member] |
Depreciation Amortization Impairment [Line Items] |
Estimated Useful Lives | 10 years
Laboratory and Office Equipment [Member] |
Depreciation Amortization Impairment [Line Items] |
Estimated Useful Lives | 5 years
Leasehold Improvements [Member] |
Depreciation Amortization Impairment [Line Items] |
Leasehold improvements | Shorter of lease term or useful life

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- Definition Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2155824 + Details
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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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