| Schedule of Investment Securities |
Investment securities consisted of the following (in thousands): | | | | | | | | | | | | | | | | | | | | | | | | | March 31, 2024 | | Amortized
Cost | | Unrealized
Gains | | Unrealized
(Losses) | | Estimated
Fair
Value | | U.S. Government Agency Securities | $ | 126,577 | | | $ | 41 | | | $ | (146) | | | $ | 126,472 | | | FDIC Certificates of Deposit | 4,165 | | | — | | | (6) | | | 4,159 | | | Certificates of Deposit | 60,000 | | | — | | | — | | | 60,000 | | | Commercial Paper | 62,031 | | | 4 | | | (35) | | | 62,000 | | | Corporate Notes/Bonds | 143,461 | | | 37 | | | (325) | | | 143,173 | | | $ | 396,234 | | | $ | 82 | | | $ | (512) | | | $ | 395,804 | |
| | | | | | | | | | | | | | | | | | | | | | | | | December 31, 2023 | | Amortized
Cost | | Unrealized
Gains | | Unrealized
(Losses) | | Estimated
Fair
Value | | U.S. Government Agency Securities | $ | 150,651 | | | $ | 148 | | | $ | (204) | | | $ | 150,595 | | | FDIC Certificates of Deposit | 4,410 | | | 2 | | | (12) | | | 4,400 | | | Certificates of Deposit | 60,000 | | | — | | | — | | | 60,000 | | | Commercial Paper | 78,610 | | | 59 | | | (27) | | | 78,642 | | | Corporate Notes/Bonds | 118,899 | | | 281 | | | (143) | | | 119,037 | | | $ | 412,570 | | | $ | 490 | | | $ | (386) | | | $ | 412,674 | |
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