Class of warrant or right warrants expiration period.

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- Definition

Number Of Common Stock Purchase Warrant

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No definition available.

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- Definition

Number Of Pre Funded Warrants

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No definition available.

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- Definition

Number Of Pre Funded Warrants To Purchase Shares Of Common Stock

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No definition available.

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- Definition

Number Of Registered Common Stock Offering

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- Definition

Number Of Shares To Purchase Upon Common Stock Purchase Warrant

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No definition available.

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- Definition

Number Of Warrants To Purchase Aggregate Shares Of Common Stock

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No definition available.

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- Definition

Offering Share Issued

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No definition available.

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- Definition

Purchase Of Common Stock Warrants Pre Funded Warrants Payable At Closing Per Share

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No definition available.

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- Definition

Purchase Of Common Stock Warrants Pre Funded Warrants Payable Upon Exercise Per Share

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No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
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- Definition

Face amount or stated value per share of common stock.

+ References

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 14
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- Definition

The cash inflow from borrowings supported by a written promise to pay an obligation that is collateralized (backed by pledge, mortgage or other lien in the entity's assets).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

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- Definition

Reduction in the number of shares during the period as a result of a reverse stock split.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 505
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- Definition

Description of the stock split arrangement. Also provide the retroactive effect given by a stock split that occurs after the balance date but before the release of financial statements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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No definition available.

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Subsequent Events - Additional Information (Detail)									1 Months Ended	12 Months Ended
Subsequent Events - Additional Information (Detail)	Jun. 04, 2018 USD ($)	May 02, 2018 $ / shares shares	Apr. 06, 2018 shares	Feb. 26, 2018 shares	Feb. 09, 2018 USD ($) $ / shares shares	Nov. 06, 2017 $ / shares shares	Jul. 21, 2016 $ / shares shares	Jul. 19, 2016 shares	Feb. 28, 2018 shares	Dec. 31, 2017 $ / shares shares	Mar. 31, 2018 $ / shares shares	Jan. 25, 2018 shares	Dec. 31, 2016 $ / shares shares	Dec. 31, 2015 $ / shares	Dec. 31, 2014 $ / shares
Subsequent Event [Line Items]
Number of pre-funded warrants									76,000
Common stock, shares issued (in shares)										228,140	896,995		24
Common stock, shares outstanding (in shares)										228,139	896,994		23
Common stock, shares authorized (in shares)								170,000,000		500,000,000	500,000,000		500,000,000
Reverse stock split ratio						0.0029	0.0625
Reverse stock split						1:350
Common stock, par value (in dollars per share) \| $ / shares							$ 0.01			$ 0.01	$ 0.01		$ 0.01
Number of fractional shares were issued in connected with the reverse stock split							0
Minimum [Member]
Subsequent Event [Line Items]
Warrants exercisable per share price (in dollars per share) \| $ / shares										1,225			281,750	$ 2,072,000	$ 4,900,000
Reverse stock split ratio								0.1
Maximum [Member]
Subsequent Event [Line Items]
Warrants exercisable per share price (in dollars per share) \| $ / shares										$ 19,712,000			$ 19,712,000	$ 19,712,000	$ 19,712,000
Reverse stock split ratio								0.05
Board of Directors [Member]
Subsequent Event [Line Items]
Common stock, shares authorized (in shares)											500,000,000
Board of Directors [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Common stock, shares authorized (in shares)				500,000,000
Reverse stock split ratio				0.01
Board of Directors [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Common stock, shares authorized (in shares)				1,000,000,000
Reverse stock split ratio				0.002
OTCQB [Member]
Subsequent Event [Line Items]
Reverse stock split ratio						0.0029
Common stock, par value (in dollars per share) \| $ / shares						$ 0.01
Number of fractional shares were issued in connected with the reverse stock split						0
Common Stock Issued [Member]
Subsequent Event [Line Items]
Number of fractional shares were issued in connected with the reverse stock split										93
Subsequent Event [Member]
Subsequent Event [Line Items]
Reverse stock split ratio		0.002
Reverse stock split		1:500
Subsequent Event [Member] \| Senior Secured Convertible Promissory Notes [Member]
Subsequent Event [Line Items]
Interest rate	8.00%
Total face amount \| $	$ 3,886,109
Purchase price \| $	$ 2,270,463
Subsequent Event [Member] \| Registered Offering [Member]
Subsequent Event [Line Items]
Number of registered common stock offering					212,000,000
Number of pre-funded warrants					38,000,000
Number of pre-funded warrants to purchase shares of common stock					38,000,000
Gross proceeds from sale of warrants \| $					$ 5,000,000
Offering price \| $ / shares					$ 0.02
Number of common stock purchase warrant					1
Number of shares to purchase upon common stock purchase warrant					2
Purchase of common stock warrants, pre-funded warrants shall be paid at offering, per unit \| $ / shares					$ 0.019
Purchase of common stock warrants, pre-funded warrants shall be paid upon exercise, per unit \| $ / shares					$ 0.001
Warrants expiration period					5 years
Warrants exercisable per share price (in dollars per share) \| $ / shares					$ 0.02
Common stock, shares issued (in shares)					434,981,824
Common stock, shares outstanding (in shares)					434,981,824
Subsequent Event [Member] \| Exchange Agreement [Member]
Subsequent Event [Line Items]
Shares issuable upon warrants exercised												108,900,000
Subsequent Event [Member] \| Board of Directors [Member]
Subsequent Event [Line Items]
Common stock, shares authorized (in shares)		1,000,000,000	1,000,000,000
Reverse stock split ratio		0.002
Reverse stock split		1-for-500
Common stock, par value (in dollars per share) \| $ / shares		$ 0.01
Subsequent Event [Member] \| Board of Directors [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Reverse stock split ratio			0.01
Reverse stock split			1-for-100
Subsequent Event [Member] \| Board of Directors [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Reverse stock split ratio			0.0020
Reverse stock split			1-for-500
Subsequent Event [Member] \| OTCQB [Member]
Subsequent Event [Line Items]
Reverse stock split ratio		0.0020
Reverse stock split		1:500
Common stock, par value (in dollars per share) \| $ / shares		$ 0.01
Number of fractional shares were issued in connected with the reverse stock split		0
Subsequent Event [Member] \| Series D Warrants [Member] \| Registered Offering [Member]
Subsequent Event [Line Items]
Number of warrants to purchase aggregate shares of common stock					500,000,000
Subsequent Event [Member] \| Common Stock Issued [Member] \| Registered Offering [Member]
Subsequent Event [Line Items]
Offering share issued					1
Subsequent Event [Member] \| Warrants [Member] \| Registered Offering [Member]
Subsequent Event [Line Items]
Offering share issued					1