| Investments |
4. Investments The fair value of available-for-sale investments by type of security was as follows:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
June 30, 2024 |
|
|
|
Amortized
Cost |
|
|
Unrealized
Gains |
|
|
Unrealized
Losses |
|
|
Fair
Value |
|
|
|
(in thousands) |
|
Investments: |
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury bills |
|
$ |
285,934 |
|
|
$ |
1 |
|
|
$ |
(565 |
) |
|
$ |
285,370 |
|
U.S. agency securities |
|
|
53,748 |
|
|
|
— |
|
|
|
(91 |
) |
|
|
53,657 |
|
Total investments with a maturity of one year or less |
|
|
339,682 |
|
|
|
1 |
|
|
|
(656 |
) |
|
|
339,027 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury bills |
|
|
193,093 |
|
|
|
8 |
|
|
|
(603 |
) |
|
|
192,498 |
|
U.S. agency securities |
|
|
22,855 |
|
|
|
1 |
|
|
|
(91 |
) |
|
|
22,765 |
|
Total investments with a maturity of one to two years |
|
|
215,948 |
|
|
|
9 |
|
|
|
(694 |
) |
|
|
215,263 |
|
Total investments |
|
$ |
555,630 |
|
|
$ |
10 |
|
|
$ |
(1,350 |
) |
|
$ |
554,290 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
December 31, 2023 |
|
|
|
Amortized
Cost |
|
|
Unrealized
Gains |
|
|
Unrealized
Losses |
|
|
Fair
Value |
|
|
|
(in thousands) |
|
Investments: |
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury bills |
|
$ |
314,957 |
|
|
$ |
83 |
|
|
$ |
(482 |
) |
|
$ |
314,558 |
|
U.S. agency securities |
|
|
185,672 |
|
|
|
24 |
|
|
|
(353 |
) |
|
|
185,343 |
|
Total investments with a maturity of one year or less |
|
|
500,629 |
|
|
|
107 |
|
|
|
(835 |
) |
|
|
499,901 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. treasury bills |
|
|
100,917 |
|
|
|
591 |
|
|
|
(58 |
) |
|
|
101,450 |
|
U.S. agency securities |
|
|
5,000 |
|
|
|
— |
|
|
|
(1 |
) |
|
|
4,999 |
|
Total investments with a maturity of one to two years |
|
|
105,917 |
|
|
|
591 |
|
|
|
(59 |
) |
|
|
106,449 |
|
Total investments |
|
$ |
606,546 |
|
|
$ |
698 |
|
|
$ |
(894 |
) |
|
$ |
606,350 |
|
The following tables summarize the Company's available-for-sale debt securities in an unrealized loss position for which an allowance for credit losses has not been recorded, aggregated by major security type and length of time in a continuous unrealized loss position:
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
June 30, 2024 |
|
|
|
Less than 12 Months |
|
|
12 Months or Longer |
|
|
Total |
|
|
|
Fair Value |
|
|
Unrealized
Losses |
|
|
Fair Value |
|
|
Unrealized
Losses |
|
|
Fair Value |
|
|
Unrealized
Losses |
|
|
|
(in thousands) |
|
U.S. treasury bills |
|
$ |
367,248 |
|
|
$ |
(957 |
) |
|
$ |
70,699 |
|
|
$ |
(211 |
) |
|
$ |
437,947 |
|
|
$ |
(1,168 |
) |
U.S. agency securities |
|
|
52,342 |
|
|
|
(167 |
) |
|
|
9,948 |
|
|
|
(15 |
) |
|
|
62,290 |
|
|
|
(182 |
) |
Total |
|
$ |
419,590 |
|
|
$ |
(1,124 |
) |
|
$ |
80,647 |
|
|
$ |
(226 |
) |
|
$ |
500,237 |
|
|
$ |
(1,350 |
) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
December 31, 2023 |
|
|
|
Less than 12 Months |
|
|
12 Months or Longer |
|
|
Total |
|
|
|
Fair Value |
|
|
Unrealized
Losses |
|
|
Fair Value |
|
|
Unrealized
Losses |
|
|
Fair Value |
|
|
Unrealized
Losses |
|
|
|
(in thousands) |
|
U.S. treasury bills |
|
$ |
172,625 |
|
|
$ |
(371 |
) |
|
$ |
27,822 |
|
|
$ |
(169 |
) |
|
$ |
200,447 |
|
|
$ |
(540 |
) |
U.S. agency securities |
|
|
136,356 |
|
|
|
(207 |
) |
|
|
36,742 |
|
|
|
(147 |
) |
|
|
173,098 |
|
|
|
(354 |
) |
Total |
|
$ |
308,981 |
|
|
$ |
(578 |
) |
|
$ |
64,564 |
|
|
$ |
(316 |
) |
|
$ |
373,545 |
|
|
$ |
(894 |
) |
As summarized in the tables immediately above, the Company held 85 and 70 debt securities that were in an unrealized loss position as of June 30, 2024 and December 31, 2023, respectively. The unrealized losses at June 30, 2024 and December 31, 2023 were attributable to changes in interest rates and do not represent credit losses. The Company does not intend to sell these securities and it is not more likely than not that it will be required to sell them before recovery of their amortized cost basis.
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