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Stockholders' Equity (Details Narrative) - USD ($) |  |  |  |  |  |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 6 Months Ended | 12 Months Ended | 65 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 27, 2018 | Oct. 27, 2017 | Oct. 27, 2017 | Oct. 04, 2017 | Jul. 06, 2017 | Jun. 09, 2017 | May 26, 2017 | May 16, 2017 | Feb. 14, 2017 | Oct. 02, 2015 | May 27, 2015 | Feb. 01, 2013 | Jan. 31, 2018 | Sep. 30, 2015 | Dec. 31, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017 | Jun. 30, 2018 | Jun. 26, 2017 | Jun. 30, 2016 | Jan. 15, 2014 | Feb. 22, 2013
Shelf registration statement amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 75,000,000 |  |  |  |  |  |  |  |  |
Common stock, shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 112,500,000 | 112,500,000 |  | 112,500,000 | 112,500,000 |  |  |  |
Preferred stock, shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100,000 | 100,000 |  | 100,000 | 100,000 |  | 100,000 |  |
Aggregate of common and preferred stock, shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 112,600,000 |  |
Reverse stock split |  |  |  |  |  |  | 14-for-1 reverse stock split |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period split stock |  |  |  |  |  |  | 14 | 56,982,418 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period reverse stock split |  |  |  |  |  |  | 14 | 4,070,172 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation arrangement by share-based payment award, options, outstanding, number, ending balance |  |  |  |  |  |  |  | 200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, outstanding |  |  |  |  |  |  |  | 2,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, par or stated value per share |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.01 | $ 0.01 |  | $ 0.01 | $ 0.01 |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 506,627 |  |  |
Class of warrant or right, exercise price of warrants or rights |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1.65 |  |  |
Proceeds from warrant exercises |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,915,286 |  |  |  |  |  |
Offering price, description |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (i) the sale of ATM Shares under the ATM Agreement having an aggregate offering price of $25 million or (ii) the termination of the ATM Agreement by Cantor or the Company. The ATM Agreement may be terminated by Cantor or the Company at any time upon 10 days' notice to the other party, or by Cantor at any time in certain circumstances, including the occurrence of a material adverse change in the Company. |  |  |  |  |  |  |
Aggregate offering price, additions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 12,200,000 |  |  |  |  |  |  |
2013 Warrants, 2014 Warrants, and June 2016 Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from warrant exercises |  |  |  |  |  | $ 2,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Increase (decrease) in fair value of warrants |  |  |  |  |  | $ 200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2015 Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from warrant exercises |  |  |  |  |  |  |  |  |  |  | $ 800,000 |  |  |  |  |  |  |  |  |  |  |  |
Increase (decrease) in fair value of warrants |  |  |  |  |  |  |  |  |  |  | 100,000 |  |  |  |  |  |  |  |  |  |  |  |
June 2016 Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from warrant exercises |  |  |  |  |  |  |  |  |  |  | $ 800,000 |  |  |  |  |  |  |  |  |  |  |  |
July 2017 Direct Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  | 2,050,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by each warrant or right |  |  |  | 4,665,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share price |  |  |  |  | $ 2.07 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock, gross |  |  |  |  | $ 4,243,500 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of warrants |  |  |  | $ 16,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
July 2017 Direct Offering [Member] | Pre-Funded Series CCC Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  |  |  |  | 385,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, offered price of warrants or rights |  |  |  |  | $ 2.06 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beneficial ownership percentage threshold |  |  |  |  | 9.99% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of warrants |  |  |  |  | $ 793,100 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, exercise price of warrants or rights |  |  |  |  | $ 0.01 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, exercised during period |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 385,000 |  |  |  |  |  |  |  |
July 2017 Direct Offering [Member] | Series AAA Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  |  |  |  | 2,435,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, exercise price of warrants or rights |  |  |  | $ 2.07 | $ 2.07 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
July 2017 Direct Offering [Member] | Series BBB Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  |  |  |  | 2,435,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, exercise price of warrants or rights |  |  |  | $ 4.75 | $ 4.75 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
July 2017 Direct Offering [Member] | Series DDD Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  |  |  | 1,166,250 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by each warrant or right |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, exercise price of warrants or rights |  |  |  | $ 6.20 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
February 14, 2017 Public Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  |  |  |  |  | 1,384,704 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued, price per share |  |  |  |  |  |  |  |  | $ 3.22 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum beneficial ownership of the purchaser |  |  |  |  |  |  |  |  | 9.99% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock |  |  |  |  |  |  |  |  | $ 5,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
February 14, 2017 Public Offering [Member] | Series AA Warrant [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  |  |  |  |  |  |  |  | 1,177,790 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, exercise price of warrants or rights |  |  |  |  |  |  |  |  | $ 3.22 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, term |  |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, exercise of warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 747,254 |  |  |  |  |
Proceeds from warrant exercises |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,400,000 |  |  |  |  |
February 14, 2017 Public Offering [Member] | Pre-Funded Series BB Warrant [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  |  |  |  |  |  |  |  | 185,713 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, exercise price of warrants or rights |  |  |  |  |  |  |  |  | $ 0.14 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued, price per share |  |  |  |  |  |  |  |  | $ 3.08 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, exercise of warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 185,713 |  |  |  |  |
May 2015 Common Stock Offering [Member] | 2015 Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  |  |  |  |  |  |  |  |  |  | 139,284 |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, exercise price of warrants or rights |  |  |  |  |  |  |  |  |  |  | $ 36.40 |  |  |  |  |  |  |  |  |  |  |  |
ATM Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  |  |  |  |  |  |  |  |  | 457,070 |  |  |  |  |  | 1,784,396 |  |  |  |
Proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,300,000 |  |  |  |  |  | $ 12,800,000 |  |  |  |
Aggregate offering price, additions |  |  |  |  |  |  |  |  |  | $ 17,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate offering price, remaining amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 12,200,000 |  |  |  |  |  |  |  |  |  |
Underwriting Agreement [Member] | Oppenheimer & Co. Inc. [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  | 2,640,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, par or stated value per share |  | $ 0.01 | $ 0.01 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  | 1,320,000 | 1,320,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant, description |  | Each share of Common Stock is being sold together with 0.5 warrants (the “Investor Warrants”), each whole Investor Warrant being exercisable for one share of Common Stock, at an offering price of $2.50 per share and related Investor Warrants. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation arrangement by share-based payment award, options, outstanding, number, ending balance |  |  |  |  |  |  |  | 2,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, outstanding |  |  |  |  |  |  |  | 33,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by each warrant or right |  | 2.325 | 2.325 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, offered price of warrants or rights |  | $ 3.00 | $ 3.00 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrants issued, expiration period | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investor Warrants [Member] | October 2017 Underwritten Offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  | 66,000 | 66,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by each warrant or right |  | 2.87 | 2.87 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrants issued, expiration period |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of common stock and warrants |  |  | $ 6,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investor Warrants [Member] | Underwriting Agreement [Member] | Oppenheimer & Co. Inc. [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by each warrant or right |  | 2.50 | 2.50 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 75,000,000 |  |
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 112,500,000 |  |
Maximum [Member] | ATM Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate offering price |  |  |  |  |  |  |  |  |  |  |  | $ 25,000,000 |  |  |  |  |  |  |  |  |  |  |
Commission on proceeds from atm shares percent |  |  |  |  |  |  |  |  |  |  |  | 3.00% |  |  |  |  |  |  |  |  |  |  |
Legal fees |  |  |  |  |  |  |  |  |  |  |  | $ 50,000 |  |  |  |  |  |  |  |  |  |  |
Maximum [Member] | Warrant [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of warrant or right, number of securities called by warrants or rights |  |  |  |  |  | 790,410 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 64,348 | 95,811
Class of warrant or right, exercise price of warrants or rights |  |  |  |  |  | $ 2.70 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 57.40 | $ 74.34

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- Definition Face amount or stated value per share of common stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
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