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Stock-Based Compensation (Tables) | 3 Months Ended
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Mar. 31, 2021
Share-based Payment Arrangement [Abstract] |
Summary of Stock Option Awards and Restricted Stock Grants | A summary of stock option awards and restricted stock grants for the three-months ended March 31, 2021 is presented below:
|  | Stock Options |  |  | Restricted Stock Awards |  |  | Weighted Average |
|  | Options Outstanding |  |  | Weighted Average Exercise Price |  |  | Non-vested Restricted Stock Outstanding |  |  | Weighted Average Grant Date Fair Value |  |  | Contractual Terms of Equity Awards (in years) |
Equity awards outstanding at January 1, 2021 |  |  | 4,624,725 |  |  | $ | 2.77 |  |  |  | 2,750 |  |  | $ | 0.89 |  |  |  |  |
Equity awards granted |  |  | 2,032,500 |  |  | $ | 2.24 |  |  |  | 1,000 |  |  | $ | 2.22 |  |  |  |  |
Equity awards exercised or vested and issued |  |  | (7,500 | ) |  | $ | 0.63 |  |  |  | - |  |  | $ | - |  |  |  |  |
Equity awards forfeited, cancelled or expired |  |  | (92,646 | ) |  | $ | 2.69 |  |  |  | - |  |  | $ | - |  |  |  |  |
Equity awards outstanding at March 31, 2021 |  |  | 6,557,079 |  |  | $ | 2.65 |  |  |  | 3,750 |  |  | $ | 1.31 |  |  |  | 8.0 |
Aggregate intrinsic value of outstanding equity awards at March 31, 2021 |  | $ | 13,163 |  |  |  |  |  |  | $ | 7,875 |  |  |  |  |  |  |  |  |
Equity awards exercisable at March 31, 2021 |  |  | 4,063,706 |  |  | $ | 2.70 |  |  |  |  |  |  |  |  |  |  |  | 7.8 |
Aggregate intrinsic value of equity awards exercisable at March 31, 2021 |  | $ | 3,300 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Assumptions Used to Determine Fair Value of Options Granted | The Company used the following assumptions for determining the fair value of options granted under the Black-Scholes option pricing model:
|  | Three Months Ended March 31, |
|  | 2021 |  |  | 2020 |
Risk-free interest rate |  |  | 1.64 to 1.74 | % |  |  | 1.33 | %
Expected volatility |  |  | 106.8 to 112.5 | % |  |  | 102.7 | %
Expected life (in years) |  |  | 7.5 to 10.0 |  |  |  | 8.5 |
Expected dividend yield |  |  | - | % |  |  | - | %

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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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