Debt and Fair Value of Financial Instruments - Fair Value of Warrants Determined by Using Option Pricing Model (Detail) - Warrant Liability [Member]	3 Months Ended
Mar. 31, 2018 $ / shares
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Expected term	5 years 6 months
Common stock market price	$ 1.75
Risk-free interest rate	2.63%
Expected volatility	72.70%
Resulting fair value (per warrant)	$ 1.04

Fair value per warrant.

No definition available.

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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

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Details

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