|
Stock Options and Warrants (Details) (USD $)
|
12 Months Ended |
|
Dec. 31, 2014
|
Dec. 31, 2013
|
Dec. 31, 2012
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
| Share-based compensation, shares subject to stock options (in shares) |
700,000 |
|
|
| Reverse stock split conversation ratio |
1-for-7 |
|
|
| Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract] |
|
|
|
| Risk-free interest rate (in hundredths) |
0.46% |
|
|
| Expected volatility (in hundredths) |
89.70% |
|
|
| Expected lives (years) |
1 year 7 months 2 days |
|
|
| Weighted-Average Exercise Price Options [Abstract] |
|
|
|
| Restricted stock expense |
$ 627,000 |
$ 186,389 |
|
| Stock-based compensation expense resulting from stock options and warrants included in the Companys Statements of Operations [Abstract] |
|
|
|
| Share-based Compensation |
6,596,248 |
3,985,106 |
2,391,529 |
| Employees [Member] |
|
|
|
| Stock-based compensation expense resulting from stock options and warrants included in the Companys Statements of Operations [Abstract] |
|
|
|
| Share-based Compensation |
3,316,106 |
2,900,564 |
1,952,950 |
| Employees [Member] | Research and development [Member] |
|
|
|
| Stock-based compensation expense resulting from stock options and warrants included in the Companys Statements of Operations [Abstract] |
|
|
|
| Share-based Compensation |
932,482 |
241,459 |
345,797 |
| Employees [Member] | General and administrative [Member] |
|
|
|
| Stock-based compensation expense resulting from stock options and warrants included in the Companys Statements of Operations [Abstract] |
|
|
|
| Share-based Compensation |
2,383,624 |
2,659,105 |
1,607,153 |
| Non-employees [Member] |
|
|
|
| Stock-based compensation expense resulting from stock options and warrants included in the Companys Statements of Operations [Abstract] |
|
|
|
| Share-based Compensation |
1,823,242 |
898,153 |
438,068 |
| Non-employees [Member] | Research and development [Member] |
|
|
|
| Stock-based compensation expense resulting from stock options and warrants included in the Companys Statements of Operations [Abstract] |
|
|
|
| Share-based Compensation |
86,539 |
0 |
0 |
| Non-employees [Member] | General and administrative [Member] |
|
|
|
| Stock-based compensation expense resulting from stock options and warrants included in the Companys Statements of Operations [Abstract] |
|
|
|
| Share-based Compensation |
$ 1,736,703 |
$ 898,153 |
$ 438,068 |
| Stock Options [Member] | Employees [Member] |
|
|
|
| Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract] |
|
|
|
| Risk-free interest rate (in hundredths) |
|
|
0.83% |
| Expected dividend yield (in hundredths) |
0.00% |
0.00% |
0.00% |
| Stock Options [Member] | Employees [Member] | Minimum [Member] |
|
|
|
| Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract] |
|
|
|
| Risk-free interest rate (in hundredths) |
1.74% |
0.91% |
1.78% |
| Expected volatility (in hundredths) |
82.00% |
85.00% |
0.00% |
| Expected lives (years) |
6 years |
6 years |
6 years |
| Stock Options [Member] | Employees [Member] | Maximum [Member] |
|
|
|
| Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract] |
|
|
|
| Risk-free interest rate (in hundredths) |
2.12% |
2.79% |
|
| Expected volatility (in hundredths) |
90.00% |
89.00% |
82.00% |
| Expected lives (years) |
10 years |
10 years |
10 years |
| Stock Options [Member] | Non-employees [Member] |
|
|
|
| Share-based compensation arrangement by share-based payment award, fair value assumptions and methodology [Abstract] |
|
|
|
| Risk-free interest rate (in hundredths) |
2.23% |
2.05% |
0.00% |
| Expected volatility (in hundredths) |
85.00% |
84.80% |
0.00% |
| Expected lives (years) |
10 years |
10 years |
0 years |
| Expected dividend yield (in hundredths) |
0.00% |
0.00% |
0.00% |
| Number of Options (Employees and Non-Employees) [Abstract] |
|
|
|
| Outstanding - beginning of year (in shares) |
167,143 |
142,143 |
143,572 |
| Granted (in shares) |
550,000 |
25,000 |
0 |
| Exercised (in shares) |
0 |
0 |
(1,429) |
| Forfeited (in shares) |
(25,000) |
0 |
0 |
| Outstanding - end of year (in shares) |
692,143 |
167,143 |
142,143 |
| Exercisable at end of year (in shares) |
692,143 |
167,143 |
133,215 |
| Weighted average fair value of stock options granted during the year (in dollars per share) |
$ 2.32 |
$ 1.98 |
$ 0 |
| Weighted-Average Exercise Price Options [Abstract] |
|
|
|
| Outstanding - beginning of year (in dollars per share) |
$ 5.69 |
$ 6.20 |
$ 6.17 |
| Granted (in dollars per share) |
$ 2.76 |
$ 2.79 |
$ 0 |
| Exercised (in dollars per share) |
$ 0 |
$ 0 |
$ 2.94 |
| Forfeited (in dollars per share) |
$ 2.79 |
$ 0 |
$ 0 |
| Outstanding - end of year (in dollars per share) |
$ 3.47 |
$ 5.69 |
$ 6.20 |
| Exercisable at end of year (in dollars per share) |
$ 3.47 |
$ 5.69 |
$ 6.10 |
| Stock Options [Member] | Employees and Directors [Member] |
|
|
|
| Number of Options (Employees and Non-Employees) [Abstract] |
|
|
|
| Outstanding - beginning of year (in shares) |
6,228,593 |
3,240,850 |
1,763,923 |
| Granted (in shares) |
3,180,000 |
3,323,176 |
1,541,002 |
| Exercised (in shares) |
(1,667) |
(476) |
(1,071) |
| Forfeited (in shares) |
(24,333) |
(127,812) |
(63,004) |
| Expired (in shares) |
(34,001) |
(207,145) |
0 |
| Outstanding - end of year (in shares) |
9,348,592 |
6,228,593 |
3,240,850 |
| Exercisable at end of year (in shares) |
4,901,511 |
3,125,720 |
1,918,461 |
| Weighted average fair value of stock options granted during the year (in dollars per share) |
$ 1.80 |
$ 1.82 |
$ 1.44 |
| Weighted-Average Exercise Price Options [Abstract] |
|
|
|
| Outstanding - beginning of year (in dollars per share) |
$ 3.11 |
$ 4.08 |
$ 6.01 |
| Granted (in dollars per share) |
$ 2.47 |
$ 2.43 |
$ 1.86 |
| Exercised (in dollars per share) |
$ 1.83 |
$ 1.93 |
$ 2.80 |
| Forfeited (in dollars per share) |
$ 2.81 |
$ 3.09 |
$ 3.89 |
| Expired (in dollars per share) |
$ 8.18 |
$ 9.59 |
$ 0 |
| Outstanding - end of year (in dollars per share) |
$ 2.83 |
$ 3.11 |
$ 4.08 |
| Exercisable at end of year (in dollars per share) |
$ 3.22 |
$ 3.86 |
$ 3.69 |
| Warrants [Member] |
|
|
|
| Number of Options (Employees and Non-Employees) [Abstract] |
|
|
|
| Outstanding - beginning of year (in shares) |
8,324,609 |
7,518,113 |
7,397,415 |
| Granted (in shares) |
25,000 |
816,667 |
285,716 |
| Exercised (in shares) |
(340,527) |
(8,572) |
(5,714) |
| Forfeited (in shares) |
0 |
0 |
(28,571) |
| Expired (in shares) |
(659,322) |
(1,599) |
(130,733) |
| Outstanding - end of year (in shares) |
7,349,760 |
8,324,609 |
7,518,113 |
| Exercisable at end of year (in shares) |
7,149,760 |
7,924,609 |
7,452,396 |
| Weighted average fair value of stock options granted during the year (in dollars per share) |
$ 3.46 |
$ 1.31 |
$ 1.22 |
| Weighted-Average Exercise Price Options [Abstract] |
|
|
|
| Outstanding - beginning of year (in dollars per share) |
$ 4.86 |
$ 5.09 |
$ 5.32 |
| Granted (in dollars per share) |
$ 5.60 |
$ 2.80 |
$ 2.06 |
| Exercised (in dollars per share) |
$ 2.56 |
$ 4.48 |
$ 1.89 |
| Forfeited (in dollars per share) |
$ 0 |
$ 0 |
$ 1.89 |
| Expired (in dollars per share) |
$ 12.66 |
$ 14.99 |
$ 11.90 |
| Outstanding - end of year (in dollars per share) |
$ 4.27 |
$ 4.86 |
$ 5.09 |
| Exercisable at end of year (in dollars per share) |
$ 4.32 |
$ 4.98 |
$ 5.11 |