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Stockholders' Equity (Details Narrative) - USD ($) |  |  |  |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 9 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 | May 27, 2015 | Aug. 31, 2018 | Sep. 30, 2015 | Dec. 31, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017 | Sep. 30, 2018 | Jun. 26, 2017 | Sep. 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 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,925,886 |  |  |  |  |  |
Aggregate offering price, additions |  |  |  |  |  |  |  |  |  |  |  |  |  | 15,000,000 |  |  |  |  |  |  |
Fair value of common stock issued as equity issuance costs and charged against paid in capital |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 450,000 |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued under the agreement |  |  |  |  | 2,050,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  |  |  |  |  |
Shares issued under the agreement |  |  |  |  |  |  |  |  | 1,384,704 |  |  |  |  |  |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  |  |  |  |
Aspire Purchase Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  |  |  |  |  |  |  | 164,835 |  |  |  |  |  |  |  |  |  |
Aggregate offering price |  |  |  |  |  |  |  |  |  |  | $ 15,000,000 |  |  |  |  |  |  |  |  |  |
Maximum number of shares purchased per day |  |  |  |  |  |  |  |  |  |  | 100,000 |  |  |  |  |  |  |  |  |  |
Maximum number of shares purchased per day, additional |  |  |  |  |  |  |  |  |  |  | 2,000,000 |  |  |  |  |  |  |  |  |  |
Aspire purchase agreement, terms |  |  |  |  |  |  |  |  |  |  | In addition, on any date on which the Company submits a Purchase Notice to Aspire Capital in an amount equal to at least 100,000 shares, the Company also has the right, in its sole discretion, to present Aspire Capital with a volume-weighted average price purchase notice (each, a “VWAP Purchase Notice”) directing Aspire Capital to purchase an amount of stock equal to up to 30% of the aggregate shares of the Company’s common stock traded on its principal market on the next trading day (the “VWAP Purchase Date”), subject to a maximum number of shares the Company may determine. The purchase price per share pursuant to such VWAP Purchase Notice is generally 97% of the volume-weighted average price for the Company’s common stock traded on its principal market on the VWAP Purchase Date |  |  |  |  |  |  |  |  |  |
Shares issued under the agreement |  |  |  |  |  |  |  |  |  |  | 164,835 |  |  |  |  |  |  |  |  |  |
ATM Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, new issues |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,784,396 |  |  |  |
Proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 12,800,000 |  |  |  |
Shares issued under the agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,784,396 |  |  |  |
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. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued under the agreement |  |  | 2,640,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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] | 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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