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Capital Structure - 20F (Details) $ / shares in Units, $ in Thousands |  |  |  |  |  |  |  |  |  |  | 1 Months Ended | 2 Months Ended | 9 Months Ended | 12 Months Ended |  |
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Aug. 10, 2016 USD ($) $ / shares shares | Oct. 21, 2015 USD ($) shares | Sep. 29, 2015 USD ($) shares | Sep. 11, 2015 USD ($) shares | Mar. 12, 2015 USD ($) $ / shares shares | Dec. 19, 2014 USD ($) $ / shares shares | Sep. 29, 2014 USD ($) $ / shares shares | Jun. 24, 2014 USD ($) $ / shares shares | Mar. 19, 2010 USD ($) shares | Feb. 03, 2010 shares | Oct. 21, 2015 USD ($) Tranche shares | Jun. 30, 2011 $ / shares | Mar. 19, 2010 USD ($) $ / shares | Sep. 30, 2016 USD ($) shares | Sep. 30, 2015 USD ($) | Dec. 31, 2015 USD ($) $ / shares shares | Dec. 31, 2014 USD ($) $ / shares shares | Dec. 31, 2013 USD ($) $ / shares | Sep. 07, 2015 $ / shares | Jan. 28, 2010 shares
Common Stock [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock (in shares) | 1,180,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock | $ | $ 4,080 |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,080 | $ 10,691 | $ 13,820 | $ 3,204 | $ 0 |  |
Price per share (in dollars per share) | $ / shares | $ 4.15 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrants and Unit Purchase Option [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant exercise price (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  | $ 19.80 | $ 19.80 |  |  |  |  |  |  |
Warrants granted during period (in shares) |  |  |  |  |  |  |  |  | 97,250 | 1,041,667 |  |  |  |  |  |  |  |  |  |
Fair value of warrants | $ |  |  |  |  |  |  |  |  | $ 1,053 |  |  |  | $ 1,053 |  |  |  |  |  |  |
Number of shares received upon exercise of warrant (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.0666667
Number of shares that can be purchased with outstanding warrants (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 15,185 |  |  |
Preferred Stock [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares issued (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  | 0 | 0 |  |  |
Dividends [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock dividend declared (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 0 | $ 0 |  |
Plaza Shipholding Corp. and Comet Shipholding Inc. [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock (in shares) |  |  |  |  |  |  | 320,000 | 378,000 |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock | $ |  |  |  |  |  |  | $ 960 | $ 1,134 |  |  |  |  |  |  |  |  |  |  |  |
Price per share (in dollars per share) | $ / shares |  |  |  |  |  |  | $ 3.00 | $ 3.00 |  |  |  |  |  |  |  |  |  |  |  |
Jelco [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock (in shares) |  | 3,476,520 | 2,655,740 | 3,889,980 | 5,000,100 | 888,000 |  |  |  |  | 10,022,240 |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock | $ |  | $ 3,129 | $ 2,390 | $ 3,501 | $ 4,500 | $ 1,110 |  |  |  |  | $ 9,020 |  |  |  |  |  |  |  |  |
Price per share (in dollars per share) | $ / shares |  |  |  |  | $ 0.90 | $ 1.25 |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.90 |
Number of tranches | Tranche |  |  |  |  |  |  |  |  |  |  | 3 |  |  |  |  |  |  |  |  |
Chief Executive Officer [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock (in shares) |  |  |  |  | 333,400 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock | $ |  |  |  |  | $ 300 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Price per share (in dollars per share) | $ / shares |  |  |  |  | $ 0.90 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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