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Stock-Based Compensation - Summary of Changes in Unvested Options (Detail) - $ / shares	12 Months Ended
	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 equity instruments options nonvested number.

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Share Based Compensation Arrangement By Share Based Payment Award Option Equity Instruments Forfeitures

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Weighted Average Grant Date Fair Values

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Share based compensation arrangement by share based payment award options cancelled in period weighted average grant date fair value.

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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.

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- Definition

Gross number of share options (or share units) granted during the period.

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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

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Number of options vested.

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Weighted average grant-date fair value of options vested.

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