Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

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- References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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- Definition

Fair Value Assumptions Number Of Nodes

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- Definition

Preferred Stock Issuance Price Per Share

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Fair Value - Schedule of Future Purchase Rights Liabilities Using Binomial Lattice Option Pricing Model (Detail)	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014 $ / shares	Dec. 31, 2013 node $ / shares	Mar. 31, 2014 $ / shares	Feb. 12, 2014 $ / shares	Dec. 01, 2013 $ / shares	Sep. 30, 2013 $ / shares	Sep. 03, 2013 $ / shares	Jun. 30, 2013 $ / shares	Mar. 31, 2013 $ / shares
Fair Value Disclosures [Abstract]
Common stock fair value (usd per share)			$ 5.93	$ 5.93	$ 11.30	$ 7.55	$ 6.77	$ 10.02	$ 9.94	$ 6.82	$ 6.85
Preferred stock price				$ 8.00
Volatility				85.00%
Risk-free interest rate				0.38%
Contractual life (years)				2 years 29 days
Number of nodes \| node				25
Dividend yield	0.00%	0.00%	0.00%	0.00%