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v3.20.4

Short-term Investments (Tables) | 12 Months Ended
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Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract] |
Summary of investments | The following is a summary of available-for-sale securities as of December 31, 2020 and 2019:
|  |  | As of December 31, 2020
| Contractual Maturity (in years) | Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Fair Market Value
Mutual funds | --- |  | $ | 153,177,675 |  |  | $ | 2,339,639 |  |  | $ | (644,140) |  |  | $ | 154,873,174 |
Certificates of deposit | Less than 1 |  | 3,000,000 |  |  | 26,260 |  |  | (10,000) |  |  | 3,016,260 |
U.S. agency mortgage-backed securities | * |  | 3,062,256 |  |  | — |  |  | (36,755) |  |  | 3,025,501 |
|  |  | $ | 159,239,931 |  |  | $ | 2,365,899 |  |  | $ | (690,895) |  |  | $ | 160,914,935 |
|  |  | 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 |
*No single maturity date.

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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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