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Stock-Based Compensation - Summary of Changes in Unvested Options (Detail) - $ / shares | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of options, Granted | 2,595,000 | 0 | 0
Unvested stock options [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of options, Granted | 2,595,000 |  |
Number of options, Vested | (135,000) |  |
Number of options, Cancelled | (38,600) |  |
Number of options, Ending balance | 1,680,000 |  |
Weighted-average grant date fair value, Granted | $ 0.45 |  |
Weighted-average grant date fair value, Vested | 0.44 |  |
Weighted-average grant date fair value, Cancelled | 14.62 |  |
Weighted-average grant date fair value, Ending balance | $ 9.97 |  |

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- Definition Share Based Compensation Arrangement By Share Based Payment Award Option Equity Instruments Forfeitures + References No definition available. + Details
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- Definition Share Based Compensation Arrangement By Share Based Payment Award Options Weighted Average Grant Date Fair Values + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average grant-date fair value of options vested. + References No definition available. + Details
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- Details
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