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v3.19.3

Investments (Tables) | 9 Months Ended
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Sep. 30, 2019
Investments |
Schedule of available-for-sale securities |
|  | September 30, 2019
|  |  |  |  | Gross |  | Gross |  |  |
|  | Amortized |  | Unrealized |  | Unrealized |  | Estimated
|  | Cost |  | Gain |  | Loss |  | Fair Value
U.S. treasury securities |  | $ | 19,982 |  | $ | 1 |  | $ | — |  | $ | 19,983
Agency bonds |  |  | 47,178 |  |  | — |  |  | (17) |  |  | 47,161
Corporate bonds |  |  | 107,045 |  |  | 20 |  |  | (62) |  |  | 107,003
Total |  | $ | 174,205 |  | $ | 21 |  | $ | (79) |  | $ | 174,147

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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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