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v3.20.1

Short-term Investments (Tables) | 12 Months Ended
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Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract] |
Summary of investments | The following is a summary of available-for-sale securities as of December 31, 2019 and 2018:
|  |  | As of December 31, 2019
| Contractual Maturity (in years) | Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Fair Market Value
Mutual funds | --- |  | $ | 66,599,219 |  |  | $ | 754,709 |  |  | $ | (15,911 | ) |  | $ | 67,338,017 |
|  |  | As of December 31, 2018
| Contractual Maturity (in years) | Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Fair Market Value
Mutual funds | --- |  | $ | 57,842,955 |  |  | $ | — |  |  | $ | (528,084 | ) |  | $ | 57,314,871 |
US corporate debt securities | Less than 2 |  | 224,633 |  |  | — |  |  | (652 | ) |  | 223,981 |
Total investments |  |  | $ | 58,067,588 |  |  | $ | — |  |  | $ | (528,736 | ) |  | $ | 57,538,852 |

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- Definition Tabular disclosure of the reconciliation of available-for-sale securities from cost basis to fair value. + References No definition available. + Details
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