Stockholders' Equity (Details) $ / shares in Units, $ in Thousands | Aug. 27, 2015USD ($)shares | May. 08, 2015USD ($) | May. 31, 2015USD ($)Closingshares | Mar. 31, 2016$ / sharesshares | Dec. 31, 2015$ / sharesshares | Dec. 31, 2014USD ($) | Dec. 17, 2015shares | Mar. 31, 2015USD ($) |
Preferred Stock [Abstract] | | | | | | | | |
Preferred stock, shares authorized (in shares) | | | | 5,000,000 | | | | |
Preferred stock, par value (in dollars per share) | $ / shares | | | | $ 0.001 | | | | |
Common Stock [Abstract] | | | | | | | | |
Number of securities callable by each unit (in shares) | | | | 16,000,000 | | | | |
Common stock, shares authorized (in shares) | | | | 75,000,000 | 290,000,000 | | | |
Series A Preferred Stock [Member] | | | | | | | | |
Preferred Stock [Abstract] | | | | | | | | |
Preferred stock, shares authorized (in shares) | | | | 5,000,000 | 5,000,000 | | | |
Preferred stock, par value (in dollars per share) | $ / shares | | | | $ 0.001 | $ 0.001 | | | |
Preferred stock, shares issued (in shares) | | | | 13,500 | 13,500 | | | |
Convertible preferred stock | | | | 3.60% | 3.60% | 3.60% | | |
Series A Preferred Stock [Member] | Dividend Declared [Member] | | | | | | | | |
Preferred Stock [Abstract] | | | | | | | | |
Dividends payable | $ | | | | | | $ 80 | | |
Series A Preferred Stock [Member] | Dividend Paid [Member] | | | | | | | | |
Preferred Stock [Abstract] | | | | | | | | |
Dividends payable | $ | | | | | | | | $ 700 |
2015 Amendment [Member] | Common Stock [Member] | | | | | | | | |
Common Stock [Abstract] | | | | | | | | |
Number of shares callable by each warrant (in shares) | | | | | | | 0.75 | |
2014 Amendment [Member] | Common Stock [Member] | | | | | | | | |
Common Stock [Abstract] | | | | | | | | |
Number of shares callable by each warrant (in shares) | | | | | | | 0.69 | |
Securities Purchase Agreement [Member] | | | | | | | | |
Common Stock [Abstract] | | | | | | | | |
Common stock issued, value | $ | | | $ 25,000 | | | | | |
Number of closings | Closing | | | 2 | | | | | |
Securities Purchase Agreement [Member] | Common Stock [Member] | | | | | | | | |
Common Stock [Abstract] | | | | | | | | |
Number of securities callable by each unit (in shares) | | | 1 | | | | | |
Number of shares callable by each warrant (in shares) | | | 1 | | | | | |
Securities Purchase Agreement [Member] | Warrants [Member] | | | | | | | | |
Common Stock [Abstract] | | | | | | | | |
Number of securities callable by each unit (in shares) | | | 1 | | | | | |
Securities Purchase Agreement [Member] | Initial Closing [Member] | | | | | | | | |
Common Stock [Abstract] | | | | | | | | |
Proceeds from private placement of stock | $ | | $ 17,400 | | | | | | |
Securities Purchase Agreement [Member] | Second Closing [Member] | | | | | | | | |
Common Stock [Abstract] | | | | | | | | |
Proceeds from private placement of stock | $ | $ 2,100 | | | | | | | |
Common stock issued (in shares) | 500,000 | | | | | | | |
Common stock, shares authorized (in shares) | 1,000,000 | | | | | | | |