| Amortized Cost, Gross Unrealized Gains (Losses) and Fair Value of Available-For-Sale Securities |
The amortized cost, gross unrealized gains (losses) and fair value of available-for-sale securities by major security type and class of security as of April 30, 2022, January 31, 2022 and April 30, 2021 were as follows:
|
|
|
Amortized |
|
|
Unrealized |
|
|
Unrealized |
|
|
Fair |
|
|
|
|
Cost |
|
|
Gains |
|
|
(Losses) |
|
|
Value |
|
|
As of April 30, 2022 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Short-term Investments: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Corporate bonds |
|
$ |
85,474 |
|
|
$ |
— |
|
|
$ |
(857 |
) |
|
$ |
84,617 |
|
|
Municipal and pre-refunded municipal bonds |
|
|
86,134 |
|
|
|
— |
|
|
|
(633 |
) |
|
|
85,501 |
|
|
US Treasury securities |
|
|
9,749 |
|
|
|
— |
|
|
|
(93 |
) |
|
|
9,656 |
|
|
Commercial paper |
|
|
7,789 |
|
|
|
— |
|
|
|
— |
|
|
|
7,789 |
|
|
|
|
|
189,146 |
|
|
|
— |
|
|
|
(1,583 |
) |
|
|
187,563 |
|
|
Long-term Investments: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Corporate bonds |
|
|
117,403 |
|
|
|
— |
|
|
|
(4,904 |
) |
|
|
112,499 |
|
|
Municipal and pre-refunded municipal bonds |
|
|
53,928 |
|
|
|
— |
|
|
|
(2,081 |
) |
|
|
51,847 |
|
|
US Treasury securities |
|
|
3,226 |
|
|
|
— |
|
|
|
(138 |
) |
|
|
3,088 |
|
|
Mutual funds, held in rabbi trust |
|
|
12,393 |
|
|
|
— |
|
|
|
(956 |
) |
|
|
11,437 |
|
|
Federal government agencies |
|
|
350 |
|
|
|
— |
|
|
|
(12 |
) |
|
|
338 |
|
|
Certificates of deposit |
|
|
249 |
|
|
|
— |
|
|
|
— |
|
|
|
249 |
|
|
|
|
|
187,549 |
|
|
|
— |
|
|
|
(8,091 |
) |
|
|
179,458 |
|
|
|
|
$ |
376,695 |
|
|
$ |
— |
|
|
$ |
(9,674 |
) |
|
$ |
367,021 |
|
|
As of January 31, 2022 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Short-term Investments: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Corporate bonds |
|
$ |
85,062 |
|
|
$ |
1 |
|
|
$ |
(200 |
) |
|
$ |
84,863 |
|
|
Municipal and pre-refunded municipal bonds |
|
|
128,984 |
|
|
|
1 |
|
|
|
(273 |
) |
|
|
128,712 |
|
|
US Treasury securities |
|
|
14,999 |
|
|
|
— |
|
|
|
(38 |
) |
|
|
14,961 |
|
|
Commercial paper |
|
|
10,884 |
|
|
|
— |
|
|
|
— |
|
|
|
10,884 |
|
|
|
|
|
239,929 |
|
|
|
2 |
|
|
|
(511 |
) |
|
|
239,420 |
|
|
Long-term Investments: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Corporate bonds |
|
|
148,830 |
|
|
|
— |
|
|
|
(2,478 |
) |
|
|
146,352 |
|
|
Municipal and pre-refunded municipal bonds |
|
|
60,533 |
|
|
|
1 |
|
|
|
(912 |
) |
|
|
59,622 |
|
|
US Treasury securities |
|
|
5,222 |
|
|
|
— |
|
|
|
(46 |
) |
|
|
5,176 |
|
|
Mutual funds, held in rabbi trust |
|
|
12,419 |
|
|
|
— |
|
|
|
(606 |
) |
|
|
11,813 |
|
|
Federal government agencies |
|
|
350 |
|
|
|
— |
|
|
|
(5 |
) |
|
|
345 |
|
|
Certificates of deposit |
|
|
249 |
|
|
|
— |
|
|
|
— |
|
|
|
249 |
|
|
|
|
|
227,603 |
|
|
|
1 |
|
|
|
(4,047 |
) |
|
|
223,557 |
|
|
|
|
$ |
467,532 |
|
|
$ |
3 |
|
|
$ |
(4,558 |
) |
|
$ |
462,977 |
|
|
|
|
Amortized |
|
|
Unrealized |
|
|
Unrealized |
|
|
Fair |
|
|
|
|
Cost |
|
|
Gains |
|
|
(Losses) |
|
|
Value |
|
|
As of April 30, 2021 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Short-term Investments: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Corporate bonds |
|
$ |
48,500 |
|
|
$ |
1 |
|
|
$ |
(49 |
) |
|
$ |
48,452 |
|
|
Municipal and pre-refunded municipal bonds |
|
|
106,266 |
|
|
|
5 |
|
|
|
(84 |
) |
|
|
106,187 |
|
|
Commercial paper |
|
|
9,791 |
|
|
|
— |
|
|
|
— |
|
|
|
9,791 |
|
|
|
|
|
164,557 |
|
|
|
6 |
|
|
|
(133 |
) |
|
|
164,430 |
|
|
Long-term Investments: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Corporate bonds |
|
|
48,850 |
|
|
|
2 |
|
|
|
(111 |
) |
|
|
48,741 |
|
|
Municipal and pre-refunded municipal bonds |
|
|
40,085 |
|
|
|
17 |
|
|
|
(48 |
) |
|
|
40,054 |
|
|
Mutual funds, held in rabbi trust |
|
|
11,448 |
|
|
|
437 |
|
|
|
— |
|
|
|
11,885 |
|
|
|
|
|
100,383 |
|
|
|
456 |
|
|
|
(159 |
) |
|
|
100,680 |
|
|
|
|
$ |
264,940 |
|
|
$ |
462 |
|
|
$ |
(292 |
) |
|
$ |
265,110 |
|
|