Available for sale securities continuous unrealized loss position for more than three months accumulated loss.

No definition available.

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- Definition

Value of input used to measure alternative investment.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

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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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No definition available.

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

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No definition available.

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Investments and Fair Value of Financial Instruments - Additional Information (Detail)	Jun. 14, 2018 $ / shares shares	Mar. 22, 2018 shares	Jun. 30, 2018 USD ($) $ / shares
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investment in continuous unrealized loss position for more than three months \| $			$ 0
Stock price \| $ / shares			$ 32.52
Measurement Input, Price Volatility [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Volatility rate			1.00
Measurement Input, Risk Free Interest Rate [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Volatility rate			0.0263
Private Placement [Member] \| Securities Purchase Agreement [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Shares of common stock issued		300,752
Common Stock Adjustment Feature Liability [Member] \| Private Placement [Member] \| Securities Purchase Agreement [Member] \| Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Shares of common stock issued		1,282,832
Common Stock Adjustment Feature Liability [Member] \| June Offering [Member] \| Securities Purchase Agreement [Member] \| Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Shares of common stock issued	1,461,962
Stock price \| $ / shares	$ 8.20
Common Stock Adjustment Feature Liability [Member] \| June Offering [Member] \| Securities Purchase Agreement [Member] \| Level 3 [Member] \| Measurement Input, Price Volatility [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Volatility rate	108
Common Stock Adjustment Feature Liability [Member] \| June Offering [Member] \| Securities Purchase Agreement [Member] \| Level 3 [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Volatility rate	2.83
Common Stock Adjustment Feature Liability [Member] \| Private Placement [Member] \| Securities Purchase Agreement [Member] \| Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Shares of common stock issued		1,201,634