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Marketable Securities (Tables) | 12 Months Ended
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Dec. 31, 2020
Marketable Securities |
Summary of investments | The following table summarizes the Company’s investments as of December 31, 2020 (in thousands):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Estimated
​ |  | Cost |  | Gains |  | Losses |  | Fair Value
Marketable securities available-for-sale: | ​ | ​ |  | ​ | ​ | ​ | ​ | ​ |  | ​ | ​ |
U.S. Treasury obligations | ​ | $ | 180,675 | ​ | $ | 7 | ​ | $ | (9) | ​ | $ | 180,673
Total available-for-sale securities | ​ | $ | 180,675 | ​ | $ | 7 | ​ | $ | (9) | ​ | $ | 180,673
​ The following table summarizes the Company’s investments as of December 31, 2019 (in thousands):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gross | ​ | ​ | ​
​ | ​ | Amortized | ​ | Unrealized | ​ | Estimated
​ |  | Cost |  | Gains |  | Losses |  | Fair Value
Marketable securities available-for-sale: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasury obligations | ​ | $ | 121,103 | ​ | $ | 39 | ​ | $ | (2) | ​ | $ | 121,140
Total available-for-sale securities | ​ | $ | 121,103 | ​ | $ | 39 | ​ | $ | (2) | ​ | $ | 121,140

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- Definition Tabular disclosure of marketable securities. This may consist of investments in certain debt and equity securities, short-term investments and other assets. + References No definition available. + Details
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